· BGP maintains a large amount of routing information and the protocols fail to complete GR when the wait timer expires. BGP will then directly advertise the routes.

For BGP to correctly advertise the routes after BGP and the protocols complete GR, set a larger wait timer for BGP. This ensures that incorrect and unreachable routes are not advertised.

Examples

# Configure BGP to wait a maximum of 600 seconds for other protocols to complete GR after BGP completes GR.

<Sysname> system-view

[Sysname] bgp 100

[Sysname-bgp-default] bgp update-delay wait-other-protocol 600

Related commands

bgp update-delay on-startup

bmp server

Use bmp server to create a BGP monitoring protocol (BMP) server and enter BMP server view.

Use undo bmp server to remove a BMP server and all its configurations.

Syntax

bmp server server-number

undo bmp server server-number

Default

No BMP servers exist.

Views

System view

Predefined user roles

network-admin

Parameters

server-number: Specifies a BMP server by its number in the range of 1 to 8.

Examples

# Create BMP server 5 and enter its view.

<Sysname> system-view

[Sysname] bmp server 5

[Sysname-bmpserver-5]

display bgp bmp server

Use display bgp bmp server to display BMP server information.

Syntax

display bgp [ instance instance-name ] bmp server server-number

Views

Any view

Predefined user roles

network-admin

network-operator

Parameters

instance instance-name: Specifies a BGP instance by its name, a case-sensitive string of 1 to 31 characters. If you do not specify this option, the command displays BMP server information for the default BGP instance.

server-number: Specifies a BMP server by its number in the range of 1 to 8.

Examples

# Display information about BMP server 1.

<Sysname> display bgp bmp server 1

BMP server number: 1

Server VPN instance name: vpna

Server address: 100.1.1.1 Server port: 6895

Client address: 100.1.1.2 Client port: 21452

BMP server state: Connected Up for 00h41m53s

Reported route mode: adj-rib-in pre-policy

Message statistics:

Total messages sent: 15

INITIATION: 1

TERMINATION: 0

STATS-REPORT: 0

PEER-UP: 4

PEER-DOWN: 3

ROUTE-MON: 7

Local RIB:

IPv4 unicast

BMP monitor BGP peers:

10.1.1.1

Table 1 Command output

Field	Description
Server VPN instance name	Name of the VPN instance to which the BMP server belongs. If the VPN instance name is followed by character string (Deleted), the VPN instance has been deleted. This field displays -- if the BMP server belongs to the public network.
Server address	IP address of the BMP server used by the TCP connection to the BMP client.
Server port	Port number of the BMP server used by the TCP connection to the BMP client.
Client address	IP address of the BMP client used by the TCP connection to the BMP server.
Client port	Port number of the BMP client used by the TCP connection to the BMP server.
BMP server state	TCP connection status: · Connected. · Not connected.
Reported route mode	Type of routes that BGP sends to the BMP server: · adj-rib-in—Send routes received from the monitored peer or peer group to the BMP server. · adj-rib-out—Send routes advertised to the monitored peer or peer group to the BMP server. · pre-policy—Send routes to the BMP server without route filtering. · post-policy—Send routes to the BMP server after route filtering. · both—Send both filtered and unfiltered routes to the BMP server. · loc-rib—Send the optimal routes in the routing table to the BMP server.
Up for	Duration of the TCP connection.
Total messages sent	Number of messages that BGP sends to the BMP server.
INITIATION	Number of initiation messages that BGP sends to the BMP server.
TERMINATION	Number of termination messages that BGP sends to the BMP server.
STATS-REPORT	Number of statistics messages that BGP sends to the BMP server.
PEER-UP	Number of peer-up messages that BGP sends to the BMP server.
PEER-DOWN	Number of peer-down messages that BGP sends to the BMP server.
ROUTE-MON	Number of route monitoring messages that BGP sends to the BMP server.
Local RIB	Optimal routes sent to the BMP server: · IPv4 unicast—BGP sends optimal IPv4 unicast routes to the BMP server. · IPv6 unicast—BGP sends optimal IPv6 unicast routes to the BMP server. · IPv4 flowspec—BGP sends optimal IPv4 flowspec routes to the BMP server. · IPv6 flowspec—BGP sends optimal IPv6 flowspec routes to the BMP server. · All-vpn-instance—BGP sends the routes of all VPN instances to the BMP server. If this field or the VPN instance: vpn-instance-name field is not displayed, BGP sends routes of the public instance to the BMP server. · VPN instance: vpn-instance-name—BGP sends routes of the VPN instance to the BMP server. If this field or the All-vpn-instance field is not displayed, BGP sends routes of the public instance to the BMP server. This field is not displayed if the route-mode loc-rib command is not configured.
BMP monitor BGP peers	Peers that are monitored by the BMP server.

‌

Related commands

reset bgp bmp server statistics

display bgp link-state

Use display bgp link-state to display BGP LS information.

Syntax

display bgp [ instance instance-name ] link-state [ ls-prefix [ advertise-info | as-path | cluster-list ] | peer { ipv4-address | ipv6-address } { advertised | received } [ statistics ] | statistics ]

Views

Any view

Predefined user roles

network-admin

network-operator

Parameters

instance instance-name: Specifies a BGP instance by its name, a case-sensitive string of 1 to 31 characters. If you do not specify this option, the command displays BGP LS information for the default BGP instance.

ls-prefix: Specifies an LS prefix. If you do not specify this argument, the command displays all BGP LS information.

advertise-info: Displays advertisement information for the specified LS prefix.

as-path: Displays AS_PATH attribute information for the specified LS prefix.

cluster-list: Displays CLUSTER_LIST attribute information for the specified LS prefix.

ipv4-address: Specifies a peer by its IPv4 address.

ipv6-address: Specifies a peer by its IPv6 address.

advertised: Displays advertised LS information.

received: Displays received LS information.

statistics: Displays statistics about LS messages.

Usage guidelines

If you do not specify any parameters, this command displays brief BGP LS route information.

Examples

# Display brief BGP LS route information for the public network.

<Sysname> display bgp link-state

Total number of routes: 2

BGP local router ID is 1.1.2.1

Status codes: * - valid, > - best, d – dampened, h – history,

s – suppressed, S – stale, i - internal, e - external

a - additional-path

Origin: i - IGP, e - EGP, ? - incomplete

Prefix codes: E link, V node, T4 IPv4 route, T6 IPv6 route, SD SRv6 SID desc

u/U unknown,

I Identifier, N local node, R remote node, L link, P prefix,

L1/L2 ISIS level-1/level-2, O OSPF, O3 OSPFv3,

D direct, S static, B BGP, SS SRv6 SID,

a area-ID, l link-ID, t topology-ID, s ISO-ID,

c confed-ID/ASN, b bgp-identifier, r router-ID,

i if-address, n peer-address, o OSPF Route-type, p IP-prefix

d designated router address/interface, ID Link Descriptor Identifer

* >e Network : [V][O][I0x0][N[c20][b1.1.1.2][a0.0.0.0][r1.1.1.2]]/376

NextHop : 1.1.1.2 LocPrf :

PrefVal : 0 OutLabel : NULL

MED :

Path/Ogn: 20i

* >e Network : [T4][O][I0x0][N[c20][b1.1.1.2][a0.0.0.0][r1.1.1.2]][P[o0x1][p1.1.1.0/24]]/480

NextHop : 1.1.1.2 LocPrf :

PrefVal : 0 OutLabel : NULL

MED :

Path/Ogn: 20i

Table 2 Command output

Field	Description
Status codes	Status codes: · * – valid—Valid route. · > – best—Optimal route. · d - dampened—Dampened route. · h – history—History route. · s – suppressed—Suppressed route. · S – stale—Stale route. · i – internal—Internal route. · e – external—External route. · a - additional-path—Add-Path optimal route.
Prefix codes	Route prefix codes: · E—Link. · V—Node. · T4—IPv4 route. · T6—IPv6 route. · SD—SRv6 SID desc. · u/U—Unknown. · I—Identifier. · N—Local node. · R—Remote node. · L—Link. · P—Prefix. · L1/L2—ISIS level-1/level-2. · O—OSPF. · O3—OSPFv3. · D—Direct. · S—Static. · B—BGP. · SS—SRv6 SID. · a—Area-ID. · l—Link-ID. · t—Topology-ID. · s—ISO-ID. · c—Confed-ID/ASN. · b—BGP-identifier. · r—Router-ID. · i—If-address. · n—Peer-address. · o—OSPF Route-type. · p—IP-prefix. · d—Designated router address/interface ID. · ID—Link descriptor identifer.
Origin	Origin of the route: · i – IGP—Originated in the AS. · e – EGP—Learned through EGP. · ? – incomplete—Unknown origin.
Network	NLRI for the LS.
NextHop	Next hop IP address.
LocPrf	Local preference.
OutLabel	This field is not supported in the current software version. Outgoing label of the route.
MED	MED attribute.
Path/Ogn	AS_PATH and ORIGIN attributes of the route: · AS_PATH—Records the ASs the route has passed, which avoids routing loops. · ORIGIN—Identifies the origin of the route.
TEPOLICY	The BGP LS route is an SR-MPLS TE policy or SRv6 TE policy route.
SEGMENT-ROUTING	Segment routing protocol.
bgp-ls-identifier	Area ID of BGP LS.
bgp-router-id	BGP router ID.
TE	Traffic engineering.
protocol-origin3	Configuration origin.
Flag	Flag.
endpoint	Destination node address.
color	Color attribute.
originator-as	AS number.
originator-address	Address identifier.
discriminator	Path identifier.

‌

# Display detailed BGP LS route information with the specified LS prefix.

<Sysname> display bgp link-state [V][O][I0x0][N[c20][b1.1.1.2][a0.0.0.0][r1.1.1.2]]/376

BGP local router ID: 1.1.1.2

Local AS number: 20

Paths: 1 available, 1 best

BGP LS information of [V][O][I0x0][N[c20][b1.1.1.2][a0.0.0.0][r1.1.1.2]]/376:

Imported route.

Original nexthop: 0.0.0.0

OutLabel : NULL

RxPathID : 0x0

TxPathID : 0xffffffff

LS : Node flag bits: 30[EA] , Local TE router ID: 3006::1

AS-path : (null)

Origin : igp

Attribute value : pref-val 32768

State : valid, local, best

IP precedence : N/A

QoS local ID : N/A

Traffic index : N/A

# Display detailed BGP LS route information with the specified LS prefix.

<Sysname> disp bgp link-state [TEPOLICY][SEGMENT-ROUTING][I0x0][N[c100][bgp-l

s-identifier11.11.11.11][bgp-router-id11.11.11.11][ipv4-router-id0.0.0.0][ipv6-r

outer-id::]][TE[protocol-origin3][Flag192][endpoint4::4][color6][originator-as0]

[originator-address::][discriminator666]]/952

BGP local router ID: 11.11.11.11

Local AS number: 100

Paths: 1 available, 1 best

BGP LS information of [TEPOLICY][SEGMENT-ROUTING][I0x0][N[c100]

[bgp-ls-identifier11.11.11.11][bgp-router-id11.11.11.11][ipv4-router-id0.0.0.0][ipv6-router-id::]][TE[protocol-origin3][Flag192][endpoint4::4][color6][originator-as0][originator-address::][discriminator666]]/952:

Imported route.

Original nexthop: 0.0.0.0

Out interface : NULL0

Route age : 00h08m03s

OutLabel : NULL

RxPathID : 0x0

TxPathID : 0xffffffff

LS : BSID:::, provisioned BSID:::, Flags(D/B/U/L/F):1/0/0/0

/1, Priority: 128, Flags(S/A/B/E/V/O/D/C/I/T): 0/1/0/1/1/0/1/0/0/1,

Preference: 666, CPathName: p6, SR Segment List:Flags:0xF

880, MTID:0, Alg:0, Weight:65535, Local Path Segment(<100::1>),Reverse

Path Segment(<200::3>)Segment(<Type, Flags, SID, SID

Descriptor>): Segment(<2,61440,400::1,0>), Binding SID:

BSID: 111::101, SRv6 Binding SID: (Flags(B/U/F):0/0/1,BSID:111::101,

SRv6 Binding SID: (Flags(B/U/F):0/0/1,BSID:111::102, Endpoint

Behavior:0xe, Flags:0x0, Algorithm:0, LBLen:48, LNLen:16, FuncLen:16,

ArgsLen:0)

AS-path : (null)

Origin : igp

Attribute value : pref-val 32768

State : valid, local, best

IP precedence : N/A

QoS local ID : N/A

Traffic index : N/A

# Display AS_PATH attribute information for the specified LS prefix.

<Sysname> display bgp link-state [V][O][I0x0][N[c20][b1.1.1.2][a0.0.0.0][r1.1.1.2]]/376 as-path

BGP local router ID: 1.1.1.2

Local AS number: 20

Paths: 1 available, 1 best

BGP LS information of [V][O][I0x0][N[c20][b1.1.1.2][a0.0.0.0][r1.1.1.2]]/376:

As-path: 100

# Display CLUSTER_LIST attribute information for the specified LS prefix.

<Sysname> display bgp link-state [V][O][I0x0][N[c20][b1.1.1.2][a0.0.0.0][r1.1.1.2]]/376 cluster-list

BGP local router ID: 1.1.1.2

Local AS number: 20

Paths: 1 available, 1 best

BGP LS information of [V][O][I0x0][N[c20][b1.1.1.2][a0.0.0.0][r1.1.1.2]]/376:

Cluster list: 100

Table 3 Command output

Field	Description
Paths	Number of routes: · available—Number of valid routes. · best—Number of optimal routes.
BGP LS information of	NLRI prefix.
Original nexthop	Original next hop of the route. If the route was obtained from a BGP update message, the original next hop is the next hop IP address in the message.
LS	LS attribute: · Node flag bits—Node attribute in hexadecimal format: ¡ 10[A]—OSPF or OSPFv3 ABR bit. ¡ 20[E]—OSPF or OSPFv3 External bit. ¡ 30[EA]—OSPF or OSPFv3 External bit and ABR bit. · Metric—Link or prefix cost. · Local TE router ID. · Average delay flag—Flag indicating whether the average delay exceeds 16777215 microseconds. ¡ 0: Stable link state whose average delay is not higher than 16777215 microseconds. ¡ 1: Unstable link state whose average delay is higher than 16777215 microseconds. · Average delay—Average delay in microseconds. · Min/Max delay flag—Flag indicating whether the Min/Max delay exceeds 16777215 microseconds. ¡ 0: Stable link state whose Min/Max delay is not higher than 16777215 microseconds. ¡ 1: Unstable link state whose Min/Max delay is higher than 16777215 microseconds. · Min delay—Minimum delay in microseconds. · Max delay—Maximum delay in microseconds. · Delay variation—Acceptable delay variation in microseconds. · Remaining bandwidth—Available bandwidth in bit/s. · Utilized bandwidth—Used bandwidth in bit/s. · SR/SRv6 capability—SR-MPLS or SRv6 capabilities: flag(O)—SRH flags OAM flag (SRH.Flags.O). 1 represents that the flag is supported. · Segment routing local block (-)—Sub-TLV information of the segment routing local block. No flag bit is defined now. This field displays a hyphen (-), and the value is fixed at 0x00. · SRLB base—Minimum label value of the SRLB range. · SRLB range—Number of labels in the SRLB. · SRv6 node MSD—Maximum SID Depths (MSD) information about the SRv6 node: ¡ MPLS MSD—Maximum number of SIDs that SR-MPLS can encapsulate in a packet. ¡ Segment Left—Maximum Segment Left value. ¡ End Pop MSD—Maximum number of SIDs that can be popped by end nodes supporting PSP or USP. ¡ T.Insert MSD—Maximum number of SIDs that the transit node can insert into a packet by using an SR policy. ¡ T.Encaps MSD—Maximum number of SIDs that the transit node can encapsulate into a packet by using an SR policy. ¡ End D MSD—Maximum number of SIDs that can be decapsulated by the end node. · SR/SRv6 link MSD—Maximum SID Depths (MSD) information about the SR or SRv6 link. ¡ MPLS MSD—Maximum number of SIDs that SR-MPLS can encapsulate in a packet. · SRv6 End.X SID—SRv6 End.X SID information: ¡ function type—SID function type. Supported types include NO-PSP, PSP, USP, USD, COC, and NEXT. ¡ algorithm—SID algorithm. 0 represent the SPF algorithm and 1 represents the strict SPF algorithm. ¡ weight—SID weight. ¡ flags(B/S/P/C)—SID flag. B represents the backup flag, S represents the set flag, P represents the persistent flag, and C represents the SRv6 compression flag. · When the C flag is set in the flags field, the following fields are displayed: ¡ Common prefix length—Length of the Common Prefix portion in the compressed SID. ¡ Node length—Length of the Node ID portion in the compressed SID. ¡ Function length—Length of the Function portion in the compressed SID. ¡ Args length—Length of the Args portion in the compressed SID. · SRv6 LAN End.X SID—SRv6 LAN End.X SID information. ¡ function type—SID function. Supported types include NO-PSP, PSP, USP, USD, COC, and NEXT. ¡ algorithm—SID algorithm. 0 represent the SPF algorithm and 1 represents the strict SPF algorithm. ¡ weight—SID weight. ¡ flags(B/S/P/C)—SID flag. B represents the backup flag, S represents the set flag, P represents the persistent flag, and C represents the SRv6 compression flag. ¡ neighbor—Neighbor node ID. This field displays system ID for IS-IS and router ID for OSPFv3. · SRv6 locator—SRv6 locator information. ¡ metric—Locator metric. ¡ algorithm—Locator algorithm. 0 represent the SPF algorithm and 1 represents the strict SPF algorithm. ¡ flags(D/A)—Locator flag. D is set when the locator is leaked to an IGP area. A is set when the locator is configured with anycast. · SRv6 SID information—SRv6 SID information: SID—SRv6 SID. · SRv6 endpoint function—SID attribute information about the SRv6 endpoint. ¡ function type—SID function type. ¡ algorithm—SID algorithm. 0 represent the SPF algorithm and 1 represents the strict SPF algorithm. · flags—SID flag. · BSID—Effective SID of the ingress node. · Provisioned BSID—Ingress node SID configured through the command. If the TE policy contains multiple BSIDs, this field displays two colons (::). · Flags(D/B/U/L/F)—Flags. ¡ D—BSID type. If this bit is set, the BSID type is IPv6. If this bit is not set, the BSID type is IPv4. ¡ B—If this bit is set, the BSID is statically assigned. ¡ U—If this bit is set, the BSID configured through the command failed to be assigned. ¡ L—If this bit is set, the BSID is assigned from SRLB. If this bit is not set, the BSID is dynamically assigned. ¡ F—If this bit is set, the BSID is dynamically assigned. · Priority—Priority. · Flags(S/A/B/E/V/O/D/C/I/T)—Flags. ¡ S—If this bit is set, the candidate path is in shutdown state. ¡ A—If this bit is set, the candidate path is active. ¡ B—If this bit is set, the candidate path is a backup path. ¡ E—If this bit is set, the candidate path is valid. ¡ V—If this bit is set, the candidate path has a minimum of one valid seglist. ¡ O—If this bit is set, the policy is generated through ODN. ¡ D—If this bit is set, the candidate path is calculated by the PCE/controller. ¡ C—If this bit is set, the candidate path is deployed by the PCE/controller. ¡ I—If this bit is set, the forwarding path is invalid and the packet is discarded. ¡ T—If this bit is set, the forwarding path is available. · Preference—Priority of the candidate path. · CPathName—Name of the candidate path. · SR Segment List—SID list. · Flags—Flags of the the SID list, which indicate the attributes and status of the SID list. This field is 2 bytes long and only the first 9 bits (D\|E\|C\|V\|R\|F\|A\|T\|M\|) are informative: ¡ D—If the SID list only contains SRv6 SIDs, this bit is set. If the SID list only contains SR-MPLS labels, this bit is not set. ¡ E—If the SID list is associated with explicit candidate paths, this bit is set. If the SID list is associated with dynamic candidate paths, this bit is not set. ¡ C—If the SID list is used to calculate dynamic paths, this bit is set. ¡ V—If the SID list has been validated or does not require validation, this bit is set. If the SID list has not been validated, this bit is not set. ¡ R—If the first segment of the SID list has been resolved, this bit is set. If the segment resolution has failed, this bit is not set. ¡ F—If the calculation of dynamic paths has failed, this bit is set. If the calculation of dynamic paths has succeeded or is not required, this bit is not set. ¡ A—If all SIDs in the SID list belong to the specified algorithm, this bit is set. ¡ T—If all SIDs in the SID list belong to the specified topology, this bit is set. ¡ M—If the SID list has been removed from the forwarding plane due to fault detection by the monitoring mechanism, this bit is set. If no failure is detected or monitoring is not performed, this bit is not set. · MTID—Multitopology ID. · Alg—ID of the algorithm used for SID list calculation. · Weight—Weight of the SID list in the candidate path. · Local Path Segment—Local path segment SID. · Reverse Path Segment—Reverse path segment SID. · Segment(<Type, Flags, SID, SID Descriptor>)—SID list information. ¡ Type—SID type. ¡ Flags—Flag. ¡ SID—SID value. ¡ SID Descriptor—SID descriptor. · Binding SID—SID of the ingress node (Based on MPLS labels). · SRv6 Binding SID: SID of the ingress node (Based on IPv6 addresses). · Flags(B/U/F): BSID flag. ¡ B—The BSID is statically assigned. ¡ U—The BSID configured by CLI failed to be assigned. ¡ F—The BSID is dynamically assigned. · Endpoint Behavior: Endpoint behavior of the SRv6 SID corresponding to the BSID. · Algorithm: Algorithm ID of the SRv6 SID corresponding to the BSID. The value of this field is fixed at 0. This field is displayed only for compressible and non-compressible hybrid SRv6 SIDs. · LBLen: Block length (G-SID common prefix length) of the SRv6 SID corresponding to the BSID. This field is displayed only for compressible and non-compressible hybrid SRv6 SIDs. · LNLen: Node ID length (IPv6 address prefix length in the locator) of the SRv6 SID corresponding to the BSID. This field is displayed only for compressible and non-compressible hybrid SRv6 SIDs. · FuncLen: Function portion length of the SRv6 SID corresponding to the BSID. This field is displayed only for compressible and non-compressible hybrid SRv6 SIDs. · ArgsLen: Argument portion length of the SRv6 SID corresponding to the BSID. This field is displayed only for compressible and non-compressible hybrid SRv6 SIDs. · Prefix Segment Identifier(Flags/Algorithm/SID): Prefix SID list information. ¡ Flags—Flag. ¡ Algorithm—Algorithm associated with the prefix. 0 represents the SPF algorithm and 1 represents the strict SPF algorithm. ¡ SID—SID value. · LAN Adjacency Segment Identifier(Flags/Weight/System-ID/SID): Adjacency SID list information. ¡ Flags—Flag. ¡ Weight—SID weight. ¡ System-ID—System ID. ¡ SID—SID value. · IPv6 LAN Adjacency Segment Identifier(Flags/Weight/System-ID/SID): IPv6 adjacency SID list information. ¡ Flags—Flag. ¡ Weight—SID weight. ¡ System-ID—System ID. ¡ SID—SID value.
RxPathID	Add-path ID of received routes.
TxPathID	Add-path ID of advertised routes.
AS-path	AS_PATH attribute of the route, which records the ASs the route has passed and avoids routing loops.
Cluster list	CLUSTER_LIST attribute of the route.
Attribute value	BGP path attributes: · MED—MED value. · localpref—Local preference value. · pref-val—Preferred value. · pre—Route preference.
State	Current state of the route: · valid. · internal. · external. · local. · synchronize. · best.
IP precedence	IP precedence in the range of 0 to 7. N/A indicates that the route does not support this field.
QoS local ID	QoS local ID in the range of 1 to 4095. N/A indicates that the route does not support this field.
Traffic index	Traffic index in the range of 1 to 64. N/A indicates that the route does not support this field.

‌

# Display advertisement information for the specified LS prefix.

<Sysname> display bgp link-state [E][B][I0x0][N[r1.1.1.2]][c65008][R[r44.33.22.11]][c65009]][L[i2.1.1.3][n1.1.1.3]]/536 advertise-info

BGP local router ID: 1.1.1.2

Local AS number: 65008

Paths: 1 best

BGP LS information of [E][B][I0x0][N[r1.1.1.2]][c65008][R[r44.33.22.11]][c65009]][L[i2.1.1.3][n1.1.1.3]]/536

(TxPathID:0):

Advertised to peers (1 in total):

10.1.1.2

LS attribute :

Peer node segment identifier : Flag c0[VL], Metric 0, Label 23001

Table 4 Command output

Field	Description
Paths	Number of routes: · available—Number of valid routes. · best—Number of optimal routes.
BGP LS information of	NLRI prefix.
Advertised to peers (1 in total)	Peers to which the information has been advertised, and the total number of such peers.
Peer node segment identifier	Peer node SID: · Flag c0[VL]: ¡ V—Value flag. If set, the SID carries a label value. ¡ L—Local flag. If set, the SID has local significance. · Metric—Link cost. · Label—Label value.
TxPathID	Add-path ID of advertised routes.

‌

# Display BGP LS route statistics.

<Sysname> display bgp link-state statistics

Total number of routes: 1

Table 5 Command output

Field	Description
Total number of routes	Total number of routes.

‌

display bgp monitor-group

Use display bgp monitor-group to display peer monitoring group information.

Syntax

display bgp [ instance instance-name ] monitor-group { all | group-name monitor-group-name }

Views

Any view

Predefined user roles

network-admin

network-operator

Parameters

instance instance-name: Specifies a BGP instance by its name, a case-sensitive string of 1 to 31 characters. If you do not specify this option, the command displays peer monitoring group information for the default BGP instance.

all: Displays information about all peer monitoring groups.

group-name monitor-group-name: Specifies a peer monitoring group by its name, a case-sensitive string of 1 to 47 characters.

Examples

# Display information about all peer monitoring groups in the default BGP instance.

<Sysname> display bgp monitor-group all

Monitor group a information:

Monitor group status : UP

Down threshold : 7

Total sessions : 7

Down sessions : 4

* - Dynamically created peer

Peer VPN State

*10.9.1.1 - INIT

*10.9.1.2 - INIT

10.2.1.2 b1 DOWN

10.2.1.2 b2 DOWN

10.2.1.2 b3 DOWN

10.3.1.2 - DOWN

10.4.1.2 - UP

Monitor group b information:

Monitor group status : DOWN

Down threshold : 4

Total sessions : 5

Down sessions : 5

* - Dynamically created peer

Peer VPN State

10.2.1.2 b1 DOWN

10.3.1.2 - DOWN

10.4.1.2 - DOWN

10.5.1.2 b1 DOWN

10.6.1.2 - DOWN

Table 6 Command output

Field	Description
Monitor group xxx information	Information about peer monitoring group xxx, where xxx represents the name of the group.
Monitor group status	Peer monitoring group state: · UP—The number of DOWN-state BGP peers in the peer monitoring group does not reach the threshold. · DOWN—The number of DOWN-state BGP peers in the peer monitoring group reaches the threshold, and all BGP sessions are disconnected.
Down threshold	Threshold for the number of DOWN-state BGP peers.
Total sessions	Number of BGP sessions in the peer monitoring group.
Down sessions	Number of disconnected BGP sessions.
* - Dynamically created peer	If a peer is marked with an asterisk (*), it is a dynamic peer.
Peer	IP address of the BGP peer.
VPN	Name of the VPN instance to which the BGP peer belongs. This field displays a hyphen (-) if the BGP peer belongs to the public instance.
State	BGP peer state. Supported states include UP, INIT, and DOWN.

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Related commands

reset monitor-group

display bgp peer received prefix-list

Use display bgp peer received prefix-list to display the ORF prefix information received by a peer.

Syntax

display bgp [ instance instance-name ] peer ipv4 [ multicast | [ unicast ] [ vpn-instance vpn-instance-name ] ] ipv4-address received prefix-list

display bgp [ instance instance-name ] peer ipv6 [ multicast | [ unicast ] [ vpn-instance vpn-instance-name ] ] ipv6-address received prefix-list

display bgp [ instance instance-name ] peer ipv4 [ unicast ] [ vpn-instance vpn-instance-name ] ipv6-address received prefix-list

display bgp [ instance instance-name ] peer ipv6 [ unicast ] [ vpn-instance vpn-instance-name ] ipv4-address received prefix-list

Views

Any view

Predefined user roles

network-admin

network-operator

Parameters

instance instance-name: Specifies a BGP instance by its name, a case-sensitive string of 1 to 31 characters. If you do not specify this option, the command displays ORF prefix information for the default BGP instance.

ipv4: Displays BGP IPv4 peer information.

ipv6: Displays BGP IPv6 peer information.

multicast: Displays BGP multicast peer information.

unicast: Displays BGP unicast peer information.

vpn-instance vpn-instance-name: Specifies a VPN instance by its name, a case-sensitive string of 1 to 31 characters. The specified VPN instance must be an MPLS L3VPN instance. If you do not specify an instance, this command displays information for the public network.

ipv4-address: Specifies a peer by its IPv4 address.

ipv6-address: Specifies a peer by its IPv6 address.

Examples

# Display the ORF prefix information received by peer 10.110.25.20.

<Sysname> display bgp peer ipv4 10.110.25.20 received prefix-list

ORF prefix list entries: 2

index: 10 prefix 1.1.1.0/24 ge 26 le 32

index: 20 prefix 2.1.1.0/24 ge 26 le 32

Table 7 Command output

Field	Description
ORF prefix list entries	Number of ORF prefixes.
index	Prefix index.
prefix	Prefix information.
ge	Greater than or equal to.
le	Less than or equal to.

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domain-distinguisher

Use domain-distinguisher to specify an AS number and a router ID for BGP LS messages.

Use undo domain-distinguisher to restore the default.

Syntax

domain-distinguisher as-number:router-id

undo domain-distinguisher

Default

The AS number and router ID of the current BGP process are used.

Views

BGP LS address family view

Predefined user roles

network-admin

Parameters

as-number:router-id: Specifies the AS number and router ID. The value range for the as-number argument is 1 to 4294967295, and the router ID is in IP address format.

Examples

# Set the AS number and router ID for BGP LS messages to 65009 and 1.1.1.1, respectively.

<Sysname> system-view

[Sysname] bgp 100

[Sysname-bgp-default] address-family link-state

[Sysname-bgp-default-ls] domain-distinguisher 65009:1.1.1.1

ebgp-interface-sensitive

Use ebgp-interface-sensitive to enable immediate re-establishment of direct EBGP sessions.

Use undo ebgp-interface-sensitive to disable immediate re-establishment of direct EBGP sessions.

Syntax

ebgp-interface-sensitive

undo ebgp-interface-sensitive

Default

Immediate re-establishment of direct EBGP sessions is enabled.

Views

BGP instance view

Predefined user roles

network-admin

Usage guidelines

When a direct link to an EBGP peer fails, BGP tears down the session and re-establishes a session to the peer immediately. If the feature is not enabled, the router does not tear down the session until the hold time expires. However, disabling this feature can prevent routing flaps from affecting EBGP session state.

This command applies only to direct EBGP sessions.

Examples

# Enable immediate re-establishment of direct EBGP sessions.

<Sysname> system-view

[Sysname] bgp 100

[Sysname-bgp-default] ebgp-interface-sensitive

fast-reroute route-policy

Use fast-reroute route-policy to apply a routing policy to fast reroute (FRR) for a BGP address family.

Use undo fast-reroute route-policy to restore the default.

Syntax

fast-reroute route-policy route-policy-name

undo fast-reroute route-policy

Default

No routing policy is applied to FRR.

Views

BGP IPv4 unicast address family view

BGP-VPN IPv4 unicast address family view

BGP IPv6 unicast address family view

BGP-VPN IPv6 unicast address family view

Predefined user roles

network-admin

Parameters

route-policy-name: Specifies a routing policy by its name, a case-sensitive string of 1 to 63 characters.

Usage guidelines

You can use the following methods to configure BGP FRR:

· Method 1—Execute the pic command in BGP address family view. BGP calculates a backup next hop for a BGP route in the address family if there are two or more unequal-cost routes to reach the destination.

· Method 2—Execute the fast-reroute route-policy command to use a routing policy in which a backup next hop is specified by using the command apply [ ipv6 ] fast-reroute backup-nexthop. For BGP to generate a backup next hop for the primary route, the backup next hop calculated by BGP must be the same as the specified backup next hop. You can also configure if-match clauses in the routing policy to identify the routes protected by FRR.

If both methods are configured, Method 2 takes precedence over Method 1.

Examples

# Apply routing policy frr-policy to FRR in BGP IPv4 unicast address family view.

<Sysname> system-view

[Sysname] bgp 100

[Sysname-bgp-default] address-family ipv4

[Sysname-bgp-default-ipv4] fast-reroute route-policy frr-policy

Related commands

apply fast-reroute

apply ipv6 fast-reroute

pic

route-policy

flush suboptimal-route

Use flush suboptimal-route to enable BGP to flush the suboptimal BGP route to the RIB.

Use undo flush suboptimal-route to disable BGP from flushing the suboptimal BGP route to the RIB.

Syntax

flush suboptimal-route

undo flush suboptimal-route

Default

BGP is disabled from flushing the suboptimal BGP route to the RIB. Only the optimal route is flushed to the RIB.

Views

BGP instance view

Predefined user roles

network-admin

Usage guidelines

This command flushes the suboptimal BGP route to the RIB when the following conditions are met:

· The optimal route is generated by the network command or is redistributed by the import-route command.

· The suboptimal route is received from a BGP peer.

After the suboptimal route is flushed to the RIB on a network, BGP immediately switches traffic to the suboptimal route when the optimal route fails.

For example, the device has a static route to the subnet 1.1.1.0/24 that has a higher priority than a BGP route. BGP redistributes the static route and receives a route to 1.1.1.0/24 from a peer. After the flush suboptimal-route command is executed, BGP flushes the received BGP route to the RIB as the suboptimal route. When the static route fails, BGP immediately switches traffic to the suboptimal route if inter-protocol FRR is enabled. For more information about inter-protocol FRR, see Layer 3—IP Routing Configuration Guide.

Examples

# Enable BGP to flush the suboptimal BGP route to the RIB.

<Sysname> system-view

[Sysname] bgp 100

[Sysname-bgp-default] flush suboptimal-route

forwarding-conversational-learning

Use forwarding-conversational-learning to enable conversational remote host route learning.

Use undo forwarding-conversational-learning to disable conversational remote host route learning.

Syntax

forwarding-conversational-learning [ route-policy route-policy-name ]

undo forwarding-conversational-learning

Default

Conversational remote host route learning is disabled in BGP IPv4 and IPv6 address family views.

In BGP EVPN address family view, conversational remote host route learning is enabled.

Views

BGP IPv4 unicast address family view

BGP IPv6 unicast address family view

Predefined user roles

network-admin

Parameters

route-policy route-policy-name: Issues only the remote host routes matching the specified routing policy to the FIB. The route-policy-name argument specifies a routing policy by its name, a case-sensitive string of 1 to 63 characters. If you do not specify a routing policy or the specified routing policy does not exist, BGP issues all remote host routes to the FIB. The apply clauses in the specified routing policy do not take effect.

Usage guidelines

By default, BGP generates FIB entries for all host routes received from peers (remote host routes) and issues the routes to the FIB. To conserve device resources, execute this command in BGP IPv4/IPv6 unicast address family view to enable conversational remote host route learning. The command enables BGP to issue a remote host route to the FIB only if it is required for forwarding a packet.

When you execute this command in BGP IPv4/IPv6 unicast address family view, follow these restrictions and guidelines:

· This command takes effect only on remote host routes generated based on ARP or ND entries and does not take effect on local host routes and other BGP routes. Host routes generated based on ARP or ND entries carry a special mark advertised through the extended community attribute. Executing this command also enables BGP to advertise the extended community attribute to all peers and peer groups.

· This command takes effect only if you execute the ip forwarding-conversational-learning command.

· The device can perform conversational learning for a remote host route only if a local interface belongs to a network segment that contains the destination address of the host route.

Examples

# In BGP IPv4 unicast address family view, enable conversational remote host route learning and specify routing policy policy1 to match remote host routes.

<Sysname>system-view

[Sysname] bgp 200

[Sysname-bgp-default] address-family ipv4 unicast

[Sysname-bgp-default-ipv4] forwarding-conversational-learning route-policy policy1

Related commands

ip forwarding-conversational-learning (EVPN Command Reference)

peer advertise-ext-community

graceful-restart

Use graceful-restart to enable BGP Graceful Restart (GR) capability.

Use undo graceful-restart to disable BGP GR capability.

Syntax

graceful-restart

undo graceful-restart

Default

BGP GR capability is disabled.

Views

BGP instance view

Predefined user roles

network-admin

Usage guidelines

GR ensures continuous forwarding when BGP restarts or an active/standby switchover occurs.

BGP peers exchange Open messages containing GR information. If both parties have GR capability, they establish a GR-capable session.

After you execute this command, the device re-establishes BGP sessions.

Examples

# Enable GR capability for BGP process 100.

<Sysname> system-view

[Sysname] bgp 100

[Sysname-bgp-default] graceful-restart

Related commands

graceful-restart timer purge-time

graceful-restart timer restart

graceful-restart timer wait-for-rib

graceful-restart peer-reset

Use graceful-restart peer-reset to enable BGP to reset peer sessions gracefully.

Use undo graceful-restart peer-reset to disable BGP from resetting peer sessions gracefully.

Syntax

graceful-restart peer-reset [ all ]

undo graceful-restart peer-reset

Default

BGP does not reset peer sessions gracefully.

Views

BGP instance view

Predefined user roles

network-admin

Parameters

all: Enables BGP to reset peer sessions gracefully when the TCP connection goes down, the hold timer expires, or the address families supporting route exchange change. If you do not specify this keyword, BGP resets peer sessions gracefully only when the address families supporting route exchange change.

Usage guidelines

When the TCP connection goes down, the hold timer expires, or the address families supporting route exchange change, BGP tears down and then re-establishes the peer sessions, which will cause traffic interruption. To avoid traffic interruption in these cases, execute this command to enable BGP to reset peer sessions gracefully.

Examples

# Enable BGP to reset peer sessions gracefully.

<Sysname> system-view

[Sysname] bgp 100

[Sysname-bgp-default] graceful-restart

[Sysname-bgp-default] graceful-restart peer-reset

Related commands

graceful-restart

graceful-restart timer purge-time

Use graceful-restart timer purge-time to set the Routing Information Base (RIB) purge timer.

Use undo graceful-restart timer purge-time to restore the default.

Syntax

graceful-restart timer purge-time timer

undo graceful-restart timer purge-time

Default

The RIB purge timer is 480 seconds.

Views

BGP instance view

Predefined user roles

network-admin

Parameters

timer: Sets the RIB purge timer in the range of 1 to 6000 seconds.

Usage guidelines

BGP starts the RIB purge timer when an active/standby switchover occurs or BGP restarts. If BGP route exchange is not completed within the RIB purge timer, the GR restarter quits the GR process. It updates the RIB with the BGP routes already learned, and removes the stale routes from RIB.

Enable BGP GR before you execute this command.

Set the RIB purge timer to be long enough to complete GR, especially when large numbers of BGP routes exist.

As a best practice, set the RIB purge timer in the following way:

· Set the timer to be greater than the timer set by the graceful-restart timer wait-for-rib command

· Set the timer to be less than the timer set by the protocol lifetime command.

Examples

# Set the RIB purge timer to 300 seconds.

<Sysname> system-view

[Sysname] bgp 100

[Sysname-bgp-default] graceful-restart

[Sysname-bgp-default] graceful-restart timer purge-time 300

Related commands

graceful-restart

graceful-restart timer restart

graceful-restart timer wait-for-rib

protocol lifetime (Layer 3—IP Routing Command Reference)

graceful-restart timer restart

Use graceful-restart timer restart to configure the GR timer.

Use undo graceful-restart timer restart to restore the default.

Syntax

graceful-restart timer restart timer

undo graceful-restart timer restart

Default

The GR timer is 150 seconds.

Views

BGP instance view

Predefined user roles

network-admin

Parameters

timer: Specifies the GR timer in the range of 3 to 600 seconds.

Usage guidelines

The GR restarter sends the GR timer to the GR helper in an Open message. When the GR helper detects that an active/standby switchover or a BGP restart occurred on the GR restarter, the GR helper performs the following operations:

1. Marks all routes learned from the GR restarter as stale.

2. Starts the GR timer.

3. If no BGP session is established before the GR timer expires, the GR helper removes the stale routes.

Before you configure this command, enable the BGP GR capability.

To apply a new GR timer, you must re-establish BGP sessions.

Examples

# Set the GR timer to 300 seconds.

<Sysname> system-view

[Sysname] bgp 100

[Sysname-bgp-default] graceful-restart

[Sysname-bgp-default] graceful-restart timer restart 300

Related commands

graceful-restart

graceful-restart timer purge-time

graceful-restart timer wait-for-rib

Use graceful-restart timer wait-for-rib to configure the time to wait for the End-of-RIB marker.

Use undo graceful-restart timer wait-for-rib to restore the default.

Syntax

graceful-restart timer wait-for-rib timer

undo graceful-restart timer wait-for-rib

Default

The time to wait for the End-of-RIB marker is 600 seconds.

Views

BGP instance view

Predefined user roles

network-admin

Parameters

timer: Specifies the time to wait for the End-of-RIB marker, in the range of 3 to 3600 seconds.

Usage guidelines

BGP uses this timer to control the time to receive updates from the peer. The timer is not advertised to the peer.

After the GR restarter and GR helper re-establish a BGP session, they start this timer. If they do not complete route exchange within the time period, the GR restarter does not receive new routes. It updates its routing table and forwarding table with learned BGP routes, and the GR helper removes the stale routes. Set a large value for the maximum time to wait for the End-of-RIB marker when a large number of routes exist.

This command controls the routing convergence speed. A smaller timer value means faster routing convergence but possibly results in incomplete routing information.

Before configuring this command, you must enable the BGP GR capability.

Examples

# Set the time to wait for the End-of-RIB marker on the local end to 100 seconds.

<Sysname> system-view

[Sysname] bgp 100

[Sysname-bgp-default] graceful-restart

[Sysname-bgp-default] graceful-restart timer wait-for-rib 100

Related commands

graceful-restart

graceful-restart timer purge-time

graceful-restart timer restart

ignore all-peers

Use ignore all-peers to disable BGP session establishment with all peers and peer groups.

Use undo ignore all-peers to restore the default.

Syntax

ignore all-peers [ graceful graceful-time { community { community-number | aa:nn } | local-preference preference | med med } * ]

undo ignore all-peers

Default

BGP can establish sessions to all peers and peer groups.

Views

BGP instance view

Predefined user roles

network-admin

Parameters

graceful graceful-time: Gracefully shuts down BGP sessions to all peers and peer groups in the specified graceful shutdown period of time. The value range for the graceful-time argument is 60 to 65535 seconds. If you set the value for this option to 0, the device does not shut down the sessions to peers and peer groups. If you do not specify this option, the command immediately shuts down the sessions to all peers and peer groups.

community { community-number | aa:nn }: Specifies the community attribute for routes advertised to all peers and peer groups. The community-number argument represents the community sequence number in the range of 1 to 4294967295. The aa:nn argument represents the community number. Both aa and nn are in the range of 0 to 65535. If you do not specify this option, the command does not change the community attribute for routes advertised to all peers and peer groups.

local-preference preference: Specifies the local preference for routes advertised to all peers and peer groups, in the range of 0 to 4294967295. A larger value represents a higher preference. If you do not specify this option, the command does not change the local preference for routes advertised to all peers and peer groups.

med med: Specifies the MED value for routes advertised to all peers and peer groups, in the range of 0 to 4294967295. The smaller the MED value, the higher the route priority. If you do not specify this option, the command does not change the MED value for routes advertised to all peers and peer groups.

Usage guidelines

CAUTION:

Executing this command tears down all existing sessions to peers and peer groups and clears all related routing information.

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This command enables you to temporarily tear down the BGP sessions to all peers and peer groups. You can perform network upgrade and maintenance without needing to delete and reconfigure the peers and peer groups. To recover the sessions, execute the undo ignore all-peers command.

If you specify the graceful keyword in the ignore all-peers command, BGP performs the following tasks:

1. Starts the wait timer specified with the graceful keyword.

2. Advertises all routes to all peers and peer groups and changes the attribute for the advertised routes to the specified value.

3. Shuts down all sessions to peers and peer groups after the wait timer expires.

This configuration lowers the priority of the routes advertised by BGP and BGP peers can select other peers' routes as optimal routes, which avoids traffic interruption upon wait timer expiration or peer disconnection. To enable BGP to advertise low-priority routes without tearing down BGP sessions, you can set the value for the graceful graceful-time option to 0.

For a BGP peer or peer group, the configuration made by the peer ignore command takes precedence over the configuration made by the ignore all-peers command.

Examples

# In BGP instance view, configure BGP to gracefully shut down the sessions to all peers and peer groups in 60 seconds, advertise all routes to all peers and peer groups, and change the community attribute and local preference for the advertised routes to 1:1 and 200, respectively.

<Sysname> system-view

[Sysname] bgp 1

[Sysname-bgp-default] ignore all-peers graceful 60 community 1:1 local-preference 200

Related commands

peer ignore

isolate enable

Use isolate enable to enable BGP isolation.

Use undo isolate enable to restore the default.

Syntax

isolate enable

undo isolate enable

Default

BGP isolation is disabled.

Views

BGP instance view

Predefined user roles

network-admin

Usage guidelines

To maintain a BGP network device, you can use BGP isolation to remove the device from the network. This feature reduces configuration workload and impact on the network by retaining the device configuration during the maintenance. After maintenance, you can disable BGP isolation to add the device back to the network.

BGP isolation works as follows:

1. BGP withdraws all routes advertised by the device except for the direct routes.

2. BGP keeps all routes learned from its peers.

3. Each peer of the device reselects an optimal route and updates the FIB table. During optimal route selection, the peers can still use the routes advertised by the device to forward traffic.

4. After an optimal route is selected and the FIB table is updated, the peers stop forwarding packets except for those destined for the device to the device. The device is fully isolated from the network and you can upgrade it.

5. After the maintenance, disable BGP isolation on the device to gracefully add it back to the network. After returning to the network, the device advertises and learns routes as follows:

¡ Advertises routes to its peers.

¡ Learns routes if BGP was reset during the isolation.

To avoid isolation failure, do not use this feature when GR is enabled for the device.

Examples

# Isolate the device from the network in BGP instance view.

<Sysname> system-view

[Sysname] bgp 100

[Sysname-bgp-default] isolate enable

monitor-group

Use monitor-group to create a peer monitoring group.

Use undo monitor-group to delete a peer monitoring group.

Syntax

monitor-group monitor-group-name threshold number

undo monitor-group monitor-group-name

Default

No peer monitoring groups exist.

Views

BGP instance view

Predefined user roles

network-admin

Parameters

monitor-group-name: Specifies a peer monitoring group by its name, a case-sensitive string of 1 to 47 characters.

threshold number: Specifies the threshold for the number of DOWN-state BGP peers, in the range of 1 to 600.

Usage guidelines

Non-default vSystems do not support this command.

Application scenarios

A peer monitoring group is mainly used in traffic switchover scenarios. For example, when the local device receives multiple BGP routes to the same destination from multiple BGP peers in AS 10 and AS 20, the traffic to that destination can be load shared between AS 10 and AS 20. If multiple BGP peers within AS 10 are disconnected from the local device, the network administrator might perceive a risk in the network status within AS 10 even if there are still running BGP sessions within the AS. The administrator might need to steer all traffic passing through AS 10 to other ASs. You can configure the peer monitoring group feature to implement automatic traffic switchover in such scenarios.

Operating mechanism

Execute the monitor-group command to create a peer monitoring group, and then execute the peer monitor-group command to add shared-risk BGP peers to the group. When the number of DOWN-state BGP peers in the group reaches the specified threshold, the local device will disconnect from all BGP peers in the group to avoid traffic loss.

Restrictions and guidelines

After the local device disconnects from all BGP peers in a peer monitoring group, the local device will not proactively establish sessions to the devices in the group. To re-establish BGP sessions to the devices in the group, execute the reset monitor-group command.

Examples

# Create BGP peer monitoring group 1, and set the threshold to four for the number of DOWN-state BGP peers.

<Sysname> system-view

[Sysname] bgp 1

[Sysname-bgp-default] monitor-group 1 threshold 4

Related commands

display bgp monitor-group

peer monitor-group

reset monitor-group

nexthop recursive-lookup delay

Use nexthop recursive-lookup delay to set the delay time for responding to recursive next hop changes.

Use undo nexthop recursive-lookup delay to disable BGP from delaying responding to recursive next hop changes.

Syntax

nexthop recursive-lookup [ non-critical-event ] delay [ delay-value ]

undo nexthop recursive-lookup [ non-critical-event ] delay

Default

BGP responds to recursive next hop changes immediately.

Views

BGP IPv4 unicast address family view

BGP IPv6 unicast address family view

BGP LS address family view

BGP-VPN IPv6 unicast address family view

BGP L2VPN address family view

BGP EVPN address family view

Predefined user roles

network-admin

Parameters

non-critical-event: Delays responding to noncritical next hop changes. If you do not specify this keyword, BGP delays responding to both critical and noncritical next hop changes.

Next hop changes include the following types:

· Critical route recursion changes—Changes that cause route unreachability and service interruption. For example, a BGP route cannot find a recursive next hop or tunnel because of network failures.

· Noncritical route recursion changes—A recursive or related route changes but the change will not cause route unreachability or service interruption. For example, the recursive interface or tunnel of a BGP route changes but traffic forwarding is not affected.

delay-value: Specifies a delay time in the range of 1 to 240 seconds. The default delay time is 5 seconds.

Usage guidelines

When recursive or related routes change frequently, configure this command to reduce unnecessary path selection and update messages and prevent traffic loss.

To avoid traffic loss, do not configure this command if only one route is available to a specific destination.

Set an appropriate delay time based on your network condition. A short delay time cannot reduce unnecessary path selection or update messages, and a long delay time might cause traffic loss.

When you configure both the nexthop recursive-lookup delay and nexthop recursive-lookup non-critical-event delay commands for an address family, follow these guidelines:

· BGP delays responding to both critical and noncritical next hop changes in the address family.

· For noncritical next hop changes, the delay time specified by the nexthop recursive-lookup non-critical-event delay command takes effect.

If you execute the nexthop recursive-lookup delay command multiple times, the most recent configuration takes effect.

If you execute the nexthop recursive-lookup non-critical-event delay command multiple times, the most recent configuration takes effect.

Examples

# In BGP IPv4 unicast address family view, set the delay time for responding to recursive next hop changes to 100 seconds.

<Sysname> system-view

[Sysname] bgp 100

[Sysname-bgp-default] address-family ipv4 unicast

[Sysname-bgp-default-ipv4] nexthop recursive-lookup delay 100

nexthop recursive-lookup longest-match

Use nexthop recursive-lookup longest-match to specify the longest match principle for BGP next hop recursion.

Use undo nexthop recursive-lookup longest-match to restore the default.

Syntax

nexthop recursive-lookup longest-match [ route-policy route-policy-name ]

undo nexthop recursive-lookup longest-match

Default

By default, BGP first looks up in its directly connected routes for a recursive route during a route recursion. If no matching routes exist, BGP will look up in routes generated by all routing protocols based on the longest match principle.

Views

BGP IPv4 unicast address family view

BGP-VPN IPv4 unicast address family view

BGP IPv6 unicast address family view

BGP-VPN IPv6 unicast address family view

Predefined user roles

network-admin

Parameters

route-policy route-policy-name: Specifies a routing policy by its name, a case-sensitive string of 1 to 63 characters.

Usage guidelines

The default method for next hop recursion might cause packet forwarding failure. The device considers the next hop of a received BGP route as directly connected when the next hop belongs to the same subnet as a direct route. As a result, packet forwarding failure will occur when the device uses this BGP route to forward matching packets.

To resolve this issue, you can use this feature to ensure the recursive route is reachable. BGP will directly look up in routes generated by all routing protocols and select a matching route based on the longest match principle.

The nexthop recursive-lookup longest-match command applies to all BGP routes received from peers in one of the following scenarios:

· The route-policy route-policy-name option is not specified.

· The specified routing policy does not exist.

Examples

# Specify the longest match principle to iterate routes that pass routing policy policy1 in BGP IPv4 unicast address family view.

<Sysname> system-view

[Sysname] bgp 100

[Sysname-bgp-default] address-family ipv4 unicast

[Sysname-bgp-default-ipv4] nexthop recursive-lookup longest-match route-policy policy1

nexthop recursive-lookup restrain

Use nexthop recursive-lookup restrain to configure BGP route recursion suppression.

Use undo nexthop recursive-lookup restrain to restore the default.

Syntax

nexthop recursive-lookup restrain { maximum-interval [ minimum-interval [ incremental-interval ] ] | millisecond interval }

undo nexthop recursive-lookup restrain

Default

BGP route recursion suppression is disabled.

Views

BGP instance view

BGP-VPN instance view

Predefined user roles

network-admin

Parameters

maximum-interval: Specifies the maximum suppression timer in the range of 1 to 60 seconds.

minimum-interval: Specifies the minimum suppression timer in the range of 10 to 60000 milliseconds. The default value is 50.

incremental-interval: Specifies the incremental timer in the range of 10 to 60000 milliseconds. The default value is 200.

millisecond interval: Specifies a fixed suppression timer in the range of 10 to 10000 milliseconds.

Usage guidelines

Application scenarios

BGP performs nexthop recursion for a BGP route to obtain a route or tunnel for real traffic forwarding. When the obtained route or tunnel changes, BGP performs nexthop recursion for the BGP route again. Upon frequent network flapping, BGP also performs route recursion repeatedly, which causes high CPU usage. To resolve this issue, configure BGP route recursion suppression. BGP can obtain the nexthop recursion result of a route only after the suppression timer expires. This feature helps reduce nexthop recursion frequency and CPU usage.

Operating mechanism

After you configure the suppression timer for route recursion, BGP can obtain the nexthop recursion result of a route only after the suppression timer expires. BGP does not update the route recursion result unless the suppression timer expires.

Restrictions and guidelines

· The value for the minimum-interval or incremental-interval argument cannot be greater than that for the maximum-interval argument.

· The view in which you should execute this command varies by next hop location as follows:

¡ If the next hop of a BGP route is on the public network, execute this command in BGP instance view.

¡ If the next hop of a BGP route is on a VPN instance, execute this command in the BGP-VPN instance view of that VPN instance.

To determine the location of a next hop, perform the following task:

a. Execute the display ip routing-table verbose or display ipv6 routing-table verbose command, find the target BGP route in the command output, and then check the value of the NibID field.

b. Execute the display rib nib or display ipv6 rib nib command with the NIB ID obtained above, and then check the value of the VrfNthp field. This field displays index of the VPN instance to which a next hop belongs.

For more information about the following commands, see IP routing basics commands in Layer 3—IP Routing Command Reference:

¡ display ip routing-table verbose

¡ display ipv6 routing-table verbose

¡ display rib nib

¡ display ipv6 rib nib

· You can execute this command multiple times with different configurations to modify the suppression timer settings. However, only the most recent configuration can take effect. The suppression timer modification does not takes effect immediately. Instead, it takes effect on the next-round route recursion.

· If you use the following commands together, BGP must wait the sum of the suppression timer and the delay timer before using the route recursion result for traffic forwarding:

¡ nexthop recursive-lookup restrain (in BGP instance view or BGP-VPN instance view)

¡ nexthop recursive-lookup delay

Examples

# In BGP instance view, set the maximum suppression timer, minimum suppression timer, and incremental timer for BGP route recursion to 60 seconds, 500 milliseconds, and 1000 milliseconds, respectively.

<Sysname> system-view

[Sysname] bgp 100

[Sysname-bgp-default] nexthop recursive-lookup restrain 60 500 1000

# In BGP instance view, set the fixed suppression timer for BGP route recursion to 1000 milliseconds.

<Sysname> system-view

[Sysname] bgp 100

[Sysname-bgp-default] nexthop recursive-lookup restrain millisecond 1000

Related commands

nexthop recursive-lookup delay

nexthop recursive-lookup route-policy

Use nexthop recursive-lookup route-policy to enable routing policy-based nexthop recursion.

Use undo nexthop recursive-lookup route-policy to restore the default.

Syntax

nexthop recursive-lookup route-policy route-policy-name

undo nexthop recursive-lookup route-policy

Default

BGP does not perform routing policy-based nexthop recursion for routes.

Views

BGP IPv4 unicast address family view

BGP-VPN IPv4 unicast address family view

BGP VPNv4 address family view

BGP-VPN VPNv4 address family view

BGP IPv6 unicast address family view

BGP LS address family view

BGP-VPN IPv6 unicast address family view

BGP VPNv6 address family view

BGP EVPN address family view

BGP IPv4 multicast address family view

BGP IPv6 multicast address family view

Predefined user roles

network-admin

Parameters

route-policy-name: Specifies a routing policy by its name, a case-sensitive string of 1 to 63 characters.

Usage guidelines

CAUTION:

Before executing this command, make sure that BGP routes can be iterated to the desired paths under the constraints of the specified routing policy. If the recursion results of a BGP route are all filtered out by the specified routing policy, BGP considers the route unreachable.

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Application scenarios

When BGP performs nexthop recursion for a route without any constraints, the route might be iterated to an incorrect traffic forwarding path. To resolve this issue, use this command to enable routing policy-based nexthop recursion. BGP can then iterate routes to the desired forwarding paths under the constraints of the specified routing policy.

Operating mechanism

With this command executed, a BGP route can take effect only when some of its nexthop recursion results can match a permit node of the specified routing policy. If the recursion results of a route are all filtered out by the specified routing policy, the route is considered unreachable and cannot take effect.

Restrictions and guidelines

· Before executing this command for an address family, perform the following task:

a. Determine the routes to which that the BGP routes in that address family can be iterated.

b. Configure a routing policy that contains the desired match criteria.

· After you execute this command for an address family, BGP reperforms next hop recursion for the routes in that address family.

· If the routing policy specified in this command does not exist, this command does not take effect. It will take effect immediately after you create the specified routing policy.

· This command does not take effect on the routes learned from directly-connected EBGP peers.

· This command does not take effect on the routes learned from the specified peer or peer group when you configure this command together with the peer nexthop-recursive-policy disable command.

· When you execute the nexthop recursive-lookup route-policy command and the protocol nexthop recursive-lookup command, follow these restrictions and guidelines:

¡ If the following conditions exist, only the nexthop recursive-lookup route-policy command takes effect on the routes in a BGP address family:

- You execute the nexthop recursive-lookup route-policy command in the view of the BGP address family.

- You execute the protocol nexthop recursive-lookup command in RIB IPv4 or IPv6 address family view.

¡ If the following conditions exist, BGP performs nexthop recursion for the routes in a BGP address family according to the configuration of the protocol nexthop recursive-lookup command in RIB IPv4 or IPv6 address family view:

- You do not execute the nexthop recursive-lookup route-policy command in the view of the BGP address family.

- You execute the protocol nexthop recursive-lookup command in RIB IPv4 or IPv6 address family view.

Examples

# In BGP IPv4 unicast address family view, specify routing policy test-policy to filter the nexthop recursion results of public BGP IPv4 unicast routes.

<Sysname> system-view

[Sysname] bgp 100

[Sysname-bgp-default] address-family ipv4 unicast

[Sysname-bgp-default-ipv6] nexthop recursive-lookup route-policy test-policy

Related commands

peer nexthop-recursive-policy disable

protocol nexthop recursive-lookup (Layer 3—IP Routing Command Reference)

peer additional-paths

Use peer additional-paths to configure the BGP Additional Paths capabilities.

Use undo peer additional-paths to remove the configuration.

Syntax

In BGP EVPN address family view:

peer { group-name | ipv4-address [ mask-length ] } additional-paths { receive | send } *

undo peer { group-name | ipv4-address [ mask-length ] } additional-paths { receive | send } *

In BGP IPv4 unicast address family view/BGP-VPN IPv4 unicast address family view/BGP IPv6 unicast address family view/BGP-VPN IPv6 unicast address family view:

peer { group-name | ipv4-address [ mask-length ] | ipv6-address [ prefix-length ] } additional-paths { receive | send } *

undo peer { group-name | ipv4-address [ mask-length ] | ipv6-address [ prefix-length ] } additional-paths { receive | send } *

Default

No BGP Additional Paths capabilities are configured.

Views

BGP IPv4 unicast address family view

BGP-VPN IPv4 unicast address family view

BGP IPv6 unicast address family view

BGP-VPN IPv6 unicast address family view

BGP EVPN address family view

Predefined user roles

network-admin

Parameters

group-name: Specifies a peer group by its name, a case-sensitive string of 1 to 47 characters. The peer group must have been created.

ipv4-address: Specifies a peer by its IPv4 address. The peer must have been created.

mask-length: Specifies a mask length in the range of 0 to 32. You can use the ipv4-address and mask-length arguments together to specify a subnet. If you specify a subnet, this command configures the BGP Additional Paths capabilities for all dynamic peers in the subnet.

ipv6-address: Specifies a peer by its IPv6 address. The peer must have been created.

prefix-length: Specifies a prefix length in the range of 0 to 128. You can use the ipv6-address and prefix-length arguments together to specify a subnet. If you specify a subnet, this command configures the BGP Additional Paths capabilities for all dynamic peers in the subnet.

receive: Enables the BGP additional path receiving capability.

send: Enables the BGP additional path sending capability.

Usage guidelines

You can enable the BGP additional path sending, receiving, or both sending and receiving capabilities on a BGP router. For two BGP peers to successfully negotiate the Additional Paths capabilities, make sure one end has the sending capability and the other end has the receiving capability.

Examples

# In BGP IPv4 unicast address family view, enable the BGP additional path receiving capability.

<Sysname> system-view

[Sysname] bgp 100

[Sysname-bgp-default] address-family ipv4 unicast

[Sysname-bgp-default-ipv4] peer 1.1.1.1 additional-paths receive

peer advertise lowest-priority track-route-policy

Use peer advertise lowest-priority track-route-policy to enable Track-based priority adjustment for BGP routes advertised to a peer or peer group

Use undo peer advertise lowest-priority track-route-policy to remove the configuration.

Syntax

peer { group-name | ipv4-address [ mask-length ] | ipv6-address [ prefix-length ] } advertise lowest-priority track-route-policy route-policy-name

undo peer { group-name | ipv4-address [ mask-length ] | ipv6-address [ prefix-length ] } advertise lowest-priority track-route-policy

Default

Track-based priority adjustment is disabled for BGP routes advertised to a peer or peer group.

Views

BGP IPv4 unicast address family view

BGP-VPN IPv4 unicast address family view

BGP IPv6 unicast address family view

BGP-VPN IPv6 unicast address family view

Predefined user roles

network-admin

Parameters

group-name: Specifies a BGP peer group by its name, a case-sensitive string of 1 to 47 characters. The peer group must have been created.

ipv4-address: Specifies a peer by its IPv4 address. The peer must have been created.

ipv6-address: Specifies a peer by its IPv6 address. The peer must have been created.

route-poicy-name: Specifies a routing policy by its name, a case-sensitive string of 1 to 63 characters.

Usage guidelines

Application scenarios

This command collaborates BGP with Track to achieve fast switchover of traffic forwarding paths in multi-level BGP networks. As shown in the following figure, two upstream BGP devices are deployed on the network, for example, Device 1 and Device 2. When all uplinks of Device 1 fail and the device cannot complete route convergence in time, the device might also fail to send route withdrawal messages to downstream devices in time. At this time, those downstream devices still forward some user traffic to Device 1, resulting in traffic forwarding failure.

Figure 1 Multi-level BGP network diagram

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To avoid this issue, enable BGP to collaborate with Track on upstream BGP devices. When uplink failures occur on an upstream BGP device, route switchover is triggered immediately and user traffic can be forwarded to another upstream BGP device with normal uplinks.

Operating mechanism

Figure 2 Track-based priority adjustment for BGP routes advertised to a peer or peer group

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To enable Track-based priority adjustment for BGP routes advertised to a downstream BGP device, perform the following operations on each upstream BGP device:

1. Associate the link state of its upstream interface with a track entry. For more information about Track, see Track configuration in High Availability Configuration Guide.

2. Execute the apply track command to configure an apply clause that references the associated track entry.

3. Execute the peer advertise lowest-priority track-route-policy command to enable BGP to collaborate with Track. The { group-name | ipv4-address [ mask-length ] | ipv6-address [ prefix-length ] } parameter specifies the desired downstream BGP device and the route-policy-name parameter specifies the routing policy configured in the previous step.

When certain uplinks of the upstream BGP device go down, the associated track entry transitions to Negative state. After perceiving the track entry state change, BGP immediately performs the following operations on the upstream BGP device:

1. Minimizes the priority of all routes advertised to the specified downstream BGP device by setting the local preference value to 0 and MED value to the maximum.

2. Advertises those routes again to the downstream BGP device.

The downstream BGP device will no longer select routes from the upstream BGP device as optimal routes and will forward user traffic to another upstream BGP device. This mechanism accelerates forwarding path switchover upon uplink failures on an upstream BGP device by skipping the process of hold timer timeout > route invalidation > route withdrawal.

Restrictions and guidelines

If a routing policy is specified in this command, only the apply track clause of that routing policy can take effect.

If the specified routing policy does not exist or it does not contain an apply track clause, this command does not take effect.

Although the peer advertise lowest-priority track-route-policy command and the peer capability-advertise withdraw-refresh command function similarly, they are different in the following aspects:

· To use the feature associated with the peer advertise lowest-priority track-route-policy command, you only need to configure this command on the desired device. The device and devices from different vendors can co-locate in the same network. However, this command cannot provide selective traffic forwarding path control, because it minimizes the priority of all routes advertised to the specified peer or peer group.

· The peer capability-advertise withdraw-refresh command can take effect only if the specified downstream BGP device supports withdrawal ROUTE-REFRESH messages. This command can provide selective traffic forwarding path control, because it can perform traffic forwarding path switchover in scenarios where only uplink failures occur.

Examples

# Enable Track-based priority adjustment for BGP routes advertised to peer 1.1.1.1.

<Sysname> system-view

[Sysname] bgp 10

[Sysname-bgp-default] address-family ipv4 unicast

[Sysname-bgp-default-vpnv4] peer 1.1.1.1 advertise lowest-priority track-route-policy 1

Related commands

apply track (Layer 3—IP Routing Command Reference)

peer advertise additional-paths best

Use peer advertise additional-paths best to set the maximum number of Add-Path optimal routes that can be advertised to a peer or peer group.

Use undo peer advertise additional-paths best to remove the configuration.

Syntax

In BGP EVPN address family view:

peer { group-name | ipv4-address [ mask-length ] } advertise additional-paths best number

undo peer { group-name | ipv4-address [ mask-length ] } advertise additional-paths best

In BGP IPv4 unicast address family view/BGP-VPN IPv4 unicast address family view/BGP IPv6 unicast address family view/BGP-VPN IPv6 unicast address family view:

peer { group-name | ipv4-address [ mask-length ] | ipv6-address [ prefix-length ] } advertise additional-paths best number

undo peer { group-name | ipv4-address [ mask-length ] | ipv6-address [ prefix-length ] } advertise additional-paths best

Default

A maximum of one Add-Path optimal route can be advertised to a peer or peer group.

Views

BGP IPv4 unicast address family view

BGP-VPN IPv4 unicast address family view

BGP IPv6 unicast address family view

BGP-VPN IPv6 unicast address family view

BGP EVPN address family view

Predefined user roles

network-admin

Parameters

group-name: Specifies a peer group by its name, a case-sensitive string of 1 to 47 characters. The peer group must have been created.

ipv4-address: Specifies a peer by its IPv4 address. The peer must have been created.

mask-length: Specifies a mask length in the range of 0 to 32. You can use the ipv4-address and mask-length arguments together to specify a subnet. If you specify a subnet, this command sets the maximum number of Add-Path optimal routes that can be advertised to all dynamic peers in the subnet.

ipv6-address: Specifies a peer by its IPv6 address. The peer must have been created.

prefix-length: Specifies a prefix length in the range of 0 to 128. You can use the ipv6-address and prefix-length arguments together to specify a subnet. If you specify a subnet, this command sets the maximum number of Add-Path optimal routes that can be advertised to all dynamic peers in the subnet.

number: Specifies the maximum number of Add-Path optimal routes that can be advertised to a peer or peer group, in the range of 2 to 64.

Usage guidelines

If the number of Add-Path optimal routes advertised to a peer or peer group exceeds the number of optimal routes, the number of optimal routes takes effect.

Examples

# In BGP IPv4 unicast address family view, set the maximum number to 3 for Add-Path optimal routes that can be advertised to peer 1.1.1.1.

<Sysname> system-view

[Sysname] bgp 100

[Sysname-bgp-default] address-family ipv4 unicast

[Sysname-bgp-default-ipv4] peer 1.1.1.1 advertise additional-paths best 3

Related commands

additional-paths select-best

peer additional-paths

peer bfd

Use peer bfd to enable BFD for the link to a BGP peer or peer group.

Use undo peer bfd to remove the configuration.

Syntax

peer { group-name | ipv4-address [ mask-length ] | ipv6-address [ prefix-length ] } bfd [ echo | multi-hop | single-hop ]

undo peer { group-name | ipv4-address [ mask-length ] | ipv6-address [ prefix-length ] } bfd

Default

BFD is disabled for the link to a BGP peer or peer group.

Views

BGP instance view

BGP-VPN instance view

Predefined user roles

network-admin

Parameters

group-name: Specifies a peer group by its name, a case-sensitive string of 1 to 47 characters. The peer group must have been created.

ipv4-address: Specifies a peer by its IPv4 address. The peer must have been created.

mask-length: Specifies a mask length in the range of 0 to 32. You can use the ipv4-address and mask-length arguments together to specify a subnet. If you specify a subnet, this command enables BFD for links to all dynamic peers in the subnet.

ipv6-address: Specifies a peer by its IPv6 address. The peer must have been created.

prefix-length: Specifies a prefix length in the range of 0 to 128. You can use the ipv6-address and prefix-length arguments together to specify a subnet. If you specify a subnet, this command enables BFD for links to all dynamic peers in the subnet.

echo: Specifies the echo packet mode for BFD.

multi-hop: Specifies the control packet mode for multi-hop BFD.

single-hop: Specifies the control packet mode for single-hop BFD.

Usage guidelines

When you do not specify the multi-hop, single-hop, or echo keyword:

· If an IBGP peer or peer group is specified, this command enables multi-hop BFD in control packet mode for the IBGP peer or peer group.

· If a directly connected EBGP peer or peer group is specified and the peer ebgp-max-hop command is not configured, this command enables single-hop BFD in control packet mode for the EBGP peer or peer group. If the EBGP peer or peer group is not directly connected or the peer ebgp-max-hop command is configured, this command enables multi-hop BFD in control packet mode for the EBGP peer or peer group.

Follow these restrictions and guidelines when you configure echo packet mode BFD:

· Echo packet mode BFD is applicable only to directly connected BGP peers.

· Echo packet mode BFD is not applicable to BGP peers established by using loopback interfaces.

· For successful BFD session establishment, make sure a source address has been specified for echo packets by using the bfd echo-source-ip or bfd echo-source-ipv6 command.

To detect the link to a BGP peer established through link-local addresses, you must configure single-hop BFD in control packet mode.

To establish a control packet mode BFD session to a BGP peer, you must configure the same BFD detection mode (multi-hop or single-hop) on the local router and the BGP peer.

For more information about BFD, see BFD configuration in High Availability Configuration Guide.

BFD helps speed up BGP routing convergence upon link failures. However, if you have enabled GR, use BFD with caution. BFD might detect a failure before the system performs GR, resulting in GR failure. If you have enabled both BFD and GR for BGP, do not disable BFD during a GR process to avoid GR failure.

Examples

# In BGP instance view, enable control packet mode single-hop BFD for the link to BGP peer group test.

<Sysname> system-view

[Sysname] bgp 100

[Sysname-bgp-default] peer test bfd single-hop

Related commands

bfd echo-source-ip (High Availability Command Reference)

bfd echo-source-ipv6 (High Availability Command Reference)

display bgp peer

display bfd session (High Availability Command Reference)

peer bfd parameters

Use peer bfd parameters to configure BFD parameters for the specified BGP peer or peer group.

Use undo peer bfd parameters to restore the default.

Syntax

peer { group-name | ipv4-address [ mask-length ] | ipv6-address [ prefix-length ] } bfd parameters { detect-multiplier detect-multiplier | min-receive-interval min-receive-interval | min-transmit-interval min-transmit-interval } *

undo peer { group-name | ipv4-address [ mask-length ] | ipv6-address [ prefix-length ] } bfd parameters { detect-multiplier | min-receive-interval | min-transmit-interval } *

Default

No BFD parameters are configured for a BGP peer or peer group.

Views

BGP instance view

BGP-VPN instance view

Predefined user roles

network-admin

Parameters

group-name: Specifies a peer group by its name, a case-sensitive string of 1 to 47 characters. The peer group must have been created.

ipv4-address: Specifies a peer by its IPv4 address. The peer must have been created.

ipv6-address: Specifies a peer by its IPv6 address. The peer must have been created.

detect-multiplier detect-multiplier: Specifies the detection time multiplier. The value range for the detect-multiplier argument is 3 to 50.

min-receive-interval min-receive-interval: Specifies the minimum interval for receiving BFD control packets, in milliseconds. The value range for the min-receive-interval argument is 100 to 10000.

min-transmit-interval min-transmit-interval: Specifies the minimum interval for transmitting BFD control packets, in milliseconds. The value range for the min-transmit-interval argument is 100 to 10000.

Usage guidelines

When you configure BFD parameters for a BGP peer or peer group, follow these restrictions and guidelines:

· When you add a peer to a peer group, the peer will inherit the BFD settings of the peer group.

· When you configure BFD parameters for a peer group, the configuration takes effect on all peers in the peer group.

· If you configure a BFD parameter multiple times for a peer or peer group, the most recent configuration takes effect.

· For a peer, the most recent configuration of a BFD parameter takes effect regardless of the configuration source.

Examples

# Configure BFD parameters for peer 2.2.2.9.

<Sysname> system-view

[Sysname] bgp 100

[Sysname-bgp-default] peer 2.2.2.9 bfd parameters min-transmit-interval 100 min-receive-interval 100 detect-multiplier 5

Related commands

display bfd session (High Availability Command Reference)

display bgp peer

peer bfd

peer bmp server

Use peer bmp server to specify a peer or peer group to be monitored by the specified BMP servers.

Use undo peer bmp server to remove the configuration.

Syntax

peer { group-name | ipv4-address [ mask-length ] | ipv6-address [ prefix-length ] } bmp server server-number-list

undo peer { group-name | ipv4-address [ mask-length ] | ipv6-address [ prefix-length ] } bmp server

Default

No peer or peer group is specified.

Views

BGP instance view

BGP-VPN instance view

Predefined user roles

network-admin

Parameters

group-name: Specifies a peer group by its name, a case-sensitive string of 1 to 47 characters. The peer group must have been created.

ipv4-address: Specifies a peer by its IPv4 address. The peer must have been created.

ipv6-address: Specifies a peer by its IPv6 address. The peer must have been created.

server-number-list: Specifies a list of up to 8 BMP servers. The value range for the BMP server number is 1 to 8. The BMP servers must have been created.

Usage guidelines

If you execute this command multiple times for a peer or peer group, the most recent configuration takes effect.

Examples

# In BGP instance view, configure BMP server 1 to monitor peer 1.1.1.1.

<Sysname> system-view

[Sysname] bgp 100

[Sysname-bgp-default] peer 1.1.1.1 bmp server 1

Related commands

bmp server

peer capability-advertise conventional

Use peer capability-advertise conventional to disable the BGP multi-protocol extension, route refresh, and 4-byte AS number features for a peer or peer group.

Use undo peer capability-advertise conventional to enable the BGP multi-protocol extension, route refresh, and 4-byte AS number features for a peer or peer group.

Syntax

peer { group-name | ipv4-address [ mask-length ] | ipv6-address [ prefix-length ] } capability-advertise conventional

undo peer { group-name | ipv4-address [ mask-length ] | ipv6-address [ prefix-length ] } capability-advertise conventional

Default

The BGP multi-protocol extension, route refresh, and 4-byte AS number features are enabled.

Views

BGP instance view

BGP-VPN instance view

Predefined user roles

network-admin

Parameters

group-name: Specifies a peer group by its name, a case-sensitive string of 1 to 47 characters. The peer group must have been created.

ipv4-address: Specifies a peer by its IPv4 address. The peer must have been created.

mask-length: Specifies a mask length in the range of 0 to 32. You can use the ipv4-address and mask-length arguments together to specify a subnet. If you specify a subnet, this command disables BGP multi-protocol extension and route refresh for all dynamic peers in the subnet.

ipv6-address: Specifies a peer by its IPv6 address. The peer must have been created.

prefix-length: Specifies a prefix length in the range of 0 to 128. You can use the ipv6-address and prefix-length arguments together to specify a subnet. If you specify a subnet, this command disables BGP multi-protocol extension and route refresh for all dynamic peers in the subnet.

Usage guidelines

The route refresh feature enables BGP to send and receive Route-refresh messages and implement BGP session soft-reset.

The multi-protocol extension feature enables BGP to advertise and receive routing information for various protocols (for example, IPv6 routing information).

The 4-byte AS number feature enables BGP to use 4-byte AS numbers in the range of 1 to 4294967295.

If both the peer capability-advertise conventional and peer capability-advertise route-refresh commands are executed, the most recent configuration takes effect.

Examples

# In BGP instance view, disable the multi-protocol extension, route refresh, and 4-byte AS number features for peer 1.1.1.1.

<Sysname> system-view

[Sysname] bgp 100

[Sysname-bgp-default] peer 1.1.1.1 as-number 100

[Sysname-bgp-default] peer 1.1.1.1 capability-advertise conventional

Related commands

display bgp peer

peer capability-advertise route-refresh

peer capability-advertise orf non-standard

Use peer capability-advertise orf non-standard to enable nonstandard ORF capabilities negotiation for a peer or peer group.

Use undo peer capability-advertise orf non-standard to disable nonstandard ORF capabilities negotiation for a peer or peer group.

Syntax

peer { group-name | ipv4-address [ mask-length ] | ipv6-address [ prefix-length ] } capability-advertise orf non-standard

undo peer { group-name | ipv4-address [ mask-length ] | ipv6-address [ prefix-length ] } capability-advertise orf non-standard

Default

Nonstandard ORF capabilities negotiation is disabled for a peer or peer group.

Views

BGP instance view

BGP-VPN instance view

Predefined user roles

network-admin

Parameters

group-name: Specifies a peer group by its name, a case-sensitive string of 1 to 47 characters. The peer group must have been created.

ipv4-address: Specifies a peer by its IPv4 address. The peer must have been created.

mask-length: Specifies a mask length in the range of 0 to 32. You can use the ip-address and mask-length arguments together to specify a subnet. If you specify a subnet, this command enables BGP to negotiate nonstandard ORF capabilities with all dynamic peers in the subnet.

ipv6-address: Specifies a peer by its IPv6 address. The peer must have been created.

prefix-length: Specifies a prefix length in the range of 0 to 128. You can use the ipv6-address and prefix-length arguments together to specify a subnet. If you specify a subnet, this command enables BGP to negotiate nonstandard ORF capabilities with all dynamic peers in the subnet.

Usage guidelines

To enable BGP peers to negotiate nonstandard ORF capabilities, you must configure this command together with the peer capability-advertise orf prefix-list command.

Examples

# Enable nonstandard ORF capabilities negotiation for peer 1.1.1.1.

<Sysname> system-view

[Sysname] bgp 100

[Sysname-bgp-default] peer 1.1.1.1 capability-advertise orf non-standard

Related commands

peer capability-advertise orf prefix-list

Use peer capability-advertise orf prefix-list to enable BGP ORF capabilities negotiation for a peer or peer group.

Use undo peer capability-advertise orf prefix-list to disable BGP ORF capabilities negotiation for a peer or peer group.

Syntax

In BGP VPNv4 address family view/BGP VPNv6 address family view/BGP IPv4 multicast address family view:

peer { group-name | ipv4-address [ mask-length ] } capability-advertise orf prefix-list { both | receive | send }

undo peer { group-name | ipv4-address [ mask-length ] } capability-advertise orf prefix-list { both | receive | send }

In BGP IPv4 unicast address family view/BGP-VPN IPv4 unicast address family view/BGP IPv6 unicast address family view/BGP-VPN IPv6 unicast address family view:

peer { group-name | ipv4-address [ mask-length ] | ipv6-address [ prefix-length ] } capability-advertise orf prefix-list { both | receive | send }

undo peer { group-name | ipv4-address [ mask-length ] | ipv6-address [ prefix-length ] } capability-advertise orf prefix-list { both | receive | send }

Default

BGP ORF capabilities are disabled.

Views

BGP IPv4 unicast address family view

BGP-VPN IPv4 unicast address family view

BGP IPv6 unicast address family view

BGP-VPN IPv6 unicast address family view

BGP IPv4 multicast address family view

Predefined user roles

network-admin

Parameters

group-name: Specifies a peer group by its name, a case-sensitive string of 1 to 47 characters. The peer group must have been created.

ipv4-address: Specifies a peer by its IPv4 address. The peer must have been created.

ipv6-address: Specifies a peer by its IPv6 address. The peer must have been created.

both: Enables BGP to send and receive route fresh messages that carry the ORF information.

receive: Enables BGP to receive route fresh messages that carry the ORF information.

send: Enables BGP to send route fresh messages that carry the ORF information.

Usage guidelines

After you configure this command, the BGP peers negotiate the ORF capabilities through Open messages. After completing the negotiation process, the BGP peers can exchange ORF information through route refresh messages. To enable the peers to exchange nonstandard ORF information, you must also configure the peer capability-advertise orf non-standard command.

Examples

# Enables BGP ORF capabilities negotiation for peer 1.1.1.1.

<Sysname> system-view

[Sysname] bgp 100

[Sysname-bgp-default] address-family ipv4

[Sysname-bgp-default-ipv4] peer 1.1.1.1 capability-advertise orf prefix-list both

Related commands

peer capability-advertise orf non-standard

peer capability-advertise route-refresh

Use peer capability-advertise route-refresh to enable BGP route refresh for a peer or peer group.

Use undo peer capability-advertise route-refresh to disable BGP route refresh for a peer or peer group.

Syntax

peer { group-name | ipv4-address [ mask-length ] | ipv6-address [ prefix-length ] } capability-advertise route-refresh

undo peer { group-name | ipv4-address [ mask-length ] | ipv6-address [ prefix-length ] } capability-advertise route-refresh

Default

BGP route refresh is enabled.

Views

BGP instance view

BGP-VPN instance view

Predefined user roles

network-admin

Parameters

group-name: Specifies a peer group by its name, a case-sensitive string of 1 to 47 characters. The peer group must have been created.

ipv4-address: Specifies a peer by its IPv4 address. The peer must have been created.

mask-length: Specifies a mask length in the range of 0 to 32. You can use the ipv4-address and mask-length arguments together to specify a subnet. If you specify a subnet, this command enables BGP route refresh for all dynamic peers in the subnet.

ipv6-address: Specifies a peer by its IPv6 address. The peer must have been created.

prefix-length: Specifies a prefix length in the range of 0 to 128. You can use the ipv6-address and prefix-length arguments together to specify a subnet. If you specify a subnet, this command enables BGP route refresh for all dynamic peers in the subnet.

Usage guidelines

The route refresh feature enables BGP to send and receive Route-refresh messages.

BGP uses the route refresh feature to implement BGP session soft-reset. After a policy is modified, the router advertises a Route-refresh message to the peers. The peers resend their routing information to the router. After receiving the routing information, the router filters the routing information by using the new policy. This method allows you to refresh the BGP routing table and apply the new route selection policy without tearing down BGP sessions.

BGP route refresh requires that both the local router and the peer support route refresh.

If both the peer capability-advertise route-refresh and peer capability-advertise conventional commands are executed, the most recent configuration takes effect.

Examples

# In BGP instance view, enable BGP route refresh for peer 1.1.1.1.

<Sysname> system-view

[Sysname] bgp 100

[Sysname-bgp-default] peer 1.1.1.1 as-number 100

[Sysname-bgp-default] peer 1.1.1.1 capability-advertise route-refresh

Related commands

display bgp peer

peer capability-advertise conventional

peer keep-all-routes

refresh bgp

peer capability-advertise suppress-4-byte-as

Use peer capability-advertise suppress-4-byte-as to enable 4-byte AS number suppression.

Use undo peer capability-advertise suppress-4-byte-as to disable 4-byte AS number suppression.

Syntax

peer { group-name | ipv4-address [ mask-length ] | ipv6-address [ prefix-length ] } capability-advertise suppress-4-byte-as

undo peer { group-name | ipv4-address [ mask-length ] | ipv6-address [ prefix-length ] } capability-advertise suppress-4-byte-as

Default

The 4-byte AS number suppression feature is disabled.

Views

BGP instance view

BGP-VPN instance view

Predefined user roles

network-admin

Parameters

group-name: Specifies a peer group by its name, a case-sensitive string of 1 to 47 characters. The peer group must have been created.

ipv4-address: Specifies a peer by its IPv4 address. The peer must have been created.

mask-length: Specifies a mask length in the range of 0 to 32. You can use the ipv4-address and mask-length arguments together to specify a subnet. If you specify a subnet, this command enables 4-byte AS number suppression for all dynamic peers in the subnet.

ipv6-address: Specifies a peer by its IPv6 address. The peer must have been created.

prefix-length: Specifies a prefix length in the range of 0 to 128. You can use the ipv6-address and prefix-length arguments together to specify a subnet. If you specify a subnet, this command enables 4-byte AS number suppression for all dynamic peers in the subnet.

Usage guidelines

CAUTION:

If the peer device supports 4-byte AS numbers, do not enable the 4-byte AS number suppression feature. If this feature is enabled, the BGP session cannot be established.

‌

BGP supports 4-byte AS numbers. The 4-byte AS number occupies four bytes, in the range of 1 to 4294967295. By default, a device sends an Open message to the peer device for session establishment. The Open message indicates that the device supports 4-byte AS numbers. If the peer device supports 2-byte AS numbers instead of 4-byte AS numbers, the session cannot be established. To resolve this issue, enable the 4-byte AS number suppression feature. The device then sends an Open message to inform the peer that it does not support 4-byte AS numbers, so the BGP session can be established.

Examples

# In BGP instance view, enable 4-byte AS number suppression for peer 1.1.1.1.

<Sysname> system-view

[Sysname] bgp 100

[Sysname-bgp-default] peer 1.1.1.1 as-number 100

[Sysname-bgp-default] peer 1.1.1.1 capability-advertise suppress-4-byte-as

Related commands

display bgp peer

pe er capability-advertise withdraw-refresh

Use peer capability-advertise withdraw-refresh to enable BGP to exchange withdrawal ROUTE-REFRESH messages with a peer or peer group.

Use undo peer capability-advertise withdraw-refresh to disable BGP from exchanging withdrawal ROUTE-REFRESH messages with a peer or peer group.

Syntax

peer { group-name | ipv4-address [ mask-length ] | ipv6-address [ prefix-length ] } capability-advertise withdraw-refresh

undo peer { group-name | ipv4-address [ mask-length ] | ipv6-address [ prefix-length ] } capability-advertise withdraw-refresh

Default

BGP cannot exchange withdrawal ROUTE-REFRESH messages with any peer or peer group.

Views

BGP instance view

BGP-VPN instance view

Predefined user roles

network-admin

Parameters

group-name: Specifies a peer group by its name, a case-sensitive string of 1 to 47 characters. The peer group must have been created.

ipv4-address: Specifies a peer by its IPv4 address. The peer must have been created.

ipv6-address: Specifies a peer by its IPv6 address. The peer must have been created.

Usage guidelines

Application scenarios

This command is applicable to multi-level BGP networking scenarios.

When all uplinks of an upstream device fail and the device cannot complete route convergence in time, the device might also fail to send route withdrawal messages to downstream devices in time. At this time, those downstream devices still forward some user traffic to the upstream device, resulting in traffic forwarding failure.

To avoid this issue, enable the upstream device to exchange withdrawal ROUTE-REFRESH messages with downstream devices. When all uplinks of the upstream device fail, it sends withdrawal ROUTE-REFRESH messages to the downstream devices. On receipt of the withdrawal ROUTE-REFRESH messages, the downstream devices immediately perform route switchover and forward traffic to another upstream device with normal uplinks.

Operating mechanism

After this command is executed on an upstream device, the upstream device performs the following operations:

1. Terminates and re-establishes the BGP session to the specified downstream device.

2. Exchanges OPEN messages with the downstream device to negotiate the capability of exchanging withdrawal ROUTE-REFRESH messages.

To ensure successful negotiation, you must configure this command at both ends of the BGP session, specifying the other end.

With the withdrawal ROUTE-REFRESH capability negotiated successfully, if the upstream device is disconnected from all peers in the same AS, it sends a withdrawal ROUTE-REFRESH message to the downstream device. The sent message carries the AS number (for example, AS 10) from which the upstream device is disconnected.

After receiving the withdrawal ROUTE-REFRESH message, the downstream device performs the following operations:

3. Searches in all BGP routes received from the upstream BGP device for routes with AS 10 as the first AS number in the NEXT_HOP attribute.

To view AS number information in the NEXT_HOP attribute of a BGP route, see the AS-path field in the output of the display rib nib or display ipv6 rib nib command.

4. After finding routes with AS 10 as the first AS number in the NEXT_HOP attribute, marks the IP routes corresponding to those routes as backup routes.

The downstream device no longer uses these routes for traffic forwarding, achieving fast route switchover.

After receiving a withdrawal ROUTE-REFRESH message, the device forwards the message to its peers as follows:

· If the message is received from an IBGP peer, the device forwards the message only to EBGP peers.

· If the message is received from an EBGP peer, the device forwards the message to IBGP peers without changing the original AS number of the message.

You can use this command in conjunction with the peer tracking command on an upstream device. The peer tracking command enables the upstream device to fast detect status of the specified BGP peer session. When the related peer is unreachable, the local device immediately terminates the BGP peer session in time and sends withdrawal ROUTE-REFRESH messages to downstream devices. Collaboration of the two commands expedites forwarding path convergence upon uplink failures.

Restrictions and guidelines

Execute this command with caution, because this operation will terminate and re-establish the BGP session between the local device and the specified peer.

This command is not applicable to scenarios where upstream devices that advertise withdrawal ROUTE-REFRESH messages are connected to IBGP peers in the uplink direction.

Examples

# In BGP instance view, enable BGP to exchange withdrawal ROUTE-REFRESH messages with peer 1.1.1.1.

<Sysname> system-view

[Sysname] bgp 100

[Sysname-bgp-default] peer 1.1.1.1 capability-advertise withdraw-refresh

Related commands

display ipv6 rib nib (Layer 3—IP Routing Command Reference)

display rib nib (Layer 3—IP Routing Command Reference)

peer tracking

peer dscp

Use peer dscp to set a DSCP value for outgoing BGP packets.

Use undo peer dscp to remove the configuration.

Syntax

peer { group-name | ipv4-address [ mask-length ] | ipv6-address [ prefix-length ] } dscp dscp-value

undo peer { group-name | ipv4-address [ mask-length ] | ipv6-address [ prefix-length ] } dscp

Default

The DSCP value for outgoing BGP packets is 48.

Views

BGP instance view

BGP-VPN instance view

Predefined user roles

network-admin

Parameters

group-name: Specifies a peer group by its name, a case-sensitive string of 1 to 47 characters. The peer group must have been created.

ipv4-address: Specifies a peer by its IPv4 address. The peer must have been created.

mask-length: Specifies a mask length in the range of 0 to 32. You can use the ipv4-address and mask-length arguments together to specify a subnet. If you specify a subnet, this command specifies a DSCP value for outgoing BGP packets to all dynamic peers in the subnet.

ipv6-address: Specifies a peer by its IPv6 address. The peer must have been created.

prefix-length: Specifies a prefix length in the range of 0 to 128. You can use the ipv6-address and prefix-length arguments together to specify a subnet. If you specify a subnet, this command specifies a DSCP value for outgoing BGP packets to all dynamic peers in the subnet.

dscp-value: Specifies a DSCP value in the range of 0 to 63.

Usage guidelines

The DSCP value of an IP packet specifies the priority level of the packet and affects the transmission priority of the packet. A larger DSCP value represents a higher priority.

Examples

# In BGP instance view, set the DSCP value to 10 for outgoing BGP packets to peer group test.

<Sysname> system-view

[Sysname] bgp 100

[Sysname-bgp-default] peer test dscp 10

peer flap-dampen

Use peer flap-dampen to configure flap dampening for a peer or peer group.

Use undo peer flap-dampen to disable flap dampening for a peer or peer group.

Syntax

peer { group-name | ipv4-address | ipv6-address } flap-dampen [ max-idle-time max-time | min-established-time min-time ]*

undo peer { group-name | ipv4-address | ipv6-address } flap-dampen

Default

Flap dampening is disabled for all peers and peer groups.

Views

BGP instance view

BGP-VPN instance view

Predefined user roles

network-admin

Parameters

group-name: Specifies a peer group by its name, a case-sensitive string of 1 to 47 characters. The peer group must have been created.

ipv4-address: Specifies a peer by its IPv4 address. The peer must have been created.

ipv6-address: Specifies a peer by its IPv6 address. The peer must have been created.

max-time: Specifies the maximum time during which a BGP peer remains in idle state. The value range for this argument is 1 to 65536 seconds, and the default value is 1800 seconds.

min-time: Specifies the minimum time during which a BGP peer remains in Established state so as to exit the dampened state. The value range for this argument is 1 to 4294967295 seconds, and the default value is 600 seconds.

Usage guidelines

Execute this command to dampen a BGP peer when the peer state frequently changes between up and down. BGP increases the idle time of the peer each time the peer comes up until the maximum idle time is reached. To exit the dampened state, the peer must remain in Established state for a time period longer than the minimum established time. After the peer exits the dampened state, BGP resets the idle time of the peer when the peer comes up again.

Set a maximum idle time and a minimum established time based on your network condition.

Examples

# In BGP instance view, enable flap dampening for peer group test, and set the maximum idle time and minimum established time to 800 seconds and 2000 seconds, respectively.

<Sysname> system-view

[Sysname] bgp 100

[Sysname-bgp-default] peer test flap-dampen max-idle-time 800 min-established-time 2000

peer graceful-restart timer restart extra

Use peer graceful-restart timer restart extra to set the extra time to wait after the restart timer expires.

Use undo peer graceful-restart timer restart extra to restore the default.

Syntax

peer { group-name | ipv4-address [ mask-length ] | ipv6-address [ prefix-length ] } graceful-restart timer restart extra { time | no-limit }

undo peer { group-name | ipv4-address [ mask-length ] | ipv6-address [ prefix-length ] } graceful-restart timer restart extra

Default

The extra time to wait after the restart timer expires is 0 seconds.

Views

BGP instance view

BGP-VPN instance view

Predefined user roles

network-admin

Parameters

group-name: Specifies a peer group by its name, a case-sensitive string of 1 to 47 characters. The peer group must have been created.

ipv4-address: Specifies a peer by its IPv4 address. The peer must have been created.

ipv6-address: Specifies a peer by its IPv6 address. The peer must have been created.

time: Specifies the extra time to wait after the restart timer expires, in the range of 0 to 86400 seconds.

no-limit: Sets an unlimited time to wait for BGP session re-establishment.

Usage guidelines

After the active/standby switchover or BGP restart completes, the GR helper marks the routes it learned from the GR restarter as stale routes. If the GR helper fails to establish a BGP session after both the GR timer and the extra timer to wait expire, the GR helper removes the stale routes.

If you specify the no-limit keyword, the GR helper does not start the End-Of-RIB marker wait timer after BGP peer session re-establishment. Instead, it keeps waiting for the End-Of-RIB marker sent from the peer.

Examples

# Set the extra time to wait after the restart timer expires to 100 seconds.

<Sysname> system-view

[Sysname] bgp 100

[Sysname-bgp-default] peer 10.1.100.2 graceful-restart timer restart extra 100

Related commands

graceful-restart timer restart

peer ignore

Use peer ignore to disable BGP session establishment with a peer or peer group.

Use undo peer ignore to enable BGP session establishment with a peer or peer group.

Syntax

peer { group-name | ipv4-address [ mask-length ] | ipv6-address [ prefix-length ] } ignore [ graceful graceful-time { community { community-number | aa:nn } | local-preference preference | med med } * ]

undo peer { group-name | ipv4-address [ mask-length ] | ipv6-address [ prefix-length ] } ignore

Default

BGP can establish a session to a peer or peer group.

Views

BGP instance view

BGP-VPN instance view

Predefined user roles

network-admin

Parameters

group-name: Specifies a peer group by its name, a case-sensitive string of 1 to 47 characters. The peer group must have been created.

ipv4-address: Specifies a peer by its IPv4 address. The peer must have been created.

mask-length: Specifies a mask length in the range of 0 to 32. You can use the ipv4-address and mask-length arguments together to specify a subnet. If you specify a subnet in this command, BGP tears down sessions to all dynamic peers in the subnet.

graceful graceful-time: Gracefully shuts down the session to a peer or peer group in the specified graceful shutdown period of time. The value range for the graceful-time argument is 60 to 65535 seconds. If you set the value for this option to 0, the device does not shut down the sessions to peers and peer groups. If you do not specify this option, the command immediately shuts down the session to the peer or peer group.

community { community-number | aa:nn }: Specifies the community attribute for advertised routes. The community-number argument represents the community sequence number in the range of 1 to 4294967295. The aa:nn argument represents the community number. Both aa and nn are in the range of 0 to 65535. If you do not specify this option, the command does not change the community attribute for advertised routes.

local-preference preference: Specifies the local preference for advertised routes, in the range of 0 to 4294967295. A larger value represents a higher preference. If you do not specify this option, the command does not change the local preference for advertised routes.

med med: Specifies the MED value for advertised routes, in the range of 0 to 4294967295. The smaller the MED value, the higher the route priority. If you do not specify this option, the command does not change the MED value for advertised routes.

ipv6-address: Specifies a peer by its IPv6 address. The peer must have been created.

prefix-length: Specifies a prefix length in the range of 0 to 128. You can use the ipv6-address and prefix-length arguments together to specify a subnet. If you specify a subnet in this command, BGP tears down sessions to all dynamic peers in the subnet.

Usage guidelines

CAUTION:

· If a session has been established to a peer, executing this command for the peer tears down the session and clears all related routing information.

· If sessions have been established to a peer group, executing this command for the peer group tears down the sessions to all peers in the group and clears all related routing information.

‌

This command enables you to temporarily tear down the BGP session to a peer or peer group. You can perform network upgrade and maintenance without needing to delete and reconfigure the peer or peer group. To recover the session, execute the undo peer ignore command.

If you specify the graceful keyword in the peer ignore command, BGP performs the following tasks:

1. Starts the wait timer specified with the graceful keyword.

2. Advertises all routes to the specified peer or peer group and changes the attribute for the advertised routes to the specified value.

Advertises the routes from the specified peer or peer group to other peers and peer groups and changes the attribute for the advertised routes to the specified value.

3. Shuts down the session to the specified peer or peer group after the wait timer expires.

For a BGP peer or peer group, the configuration made by the peer ignore command takes precedence over the configuration made by the ignore all-peers command.

Examples

# In BGP instance view, disable session establishment with peer 1.1.1.1.

<Sysname> system-view

[Sysname] bgp 100

[Sysname-bgp-default] peer 1.1.1.1 ignore

# In BGP instance view, configure BGP to gracefully shut down the session to peer 1.1.1.1 in 60 seconds, advertise all routes to peer 1.1.1.1, and change the community attribute and local preference for the advertised routes to 1:1 and 200, respectively.

<Sysname> system-view

[Sysname] bgp 1

[Sysname-bgp-default] peer 1.1.1.1 ignore graceful 60 community 1:1 local-preference 200

Related commands

ignore all-peers

peer keep-all-routes

Use peer keep-all-routes to save all route updates from a peer or peer group, regardless of whether the routes have passed the configured routing policy.

Use undo peer keep-all-routes to remove the configuration.

Syntax

peer { group-name | ipv4-address [ mask-length ] } keep-all-routes

undo peer { group-name | ipv4-address [ mask-length ] } keep-all-routes

In BGP IPv4 unicast address family view/BGP-VPN IPv4 unicast address family view:

peer { group-name | ipv4-address [ mask-length ] | ipv6-address [ prefix-length ] } keep-all-routes

undo peer { group-name | ipv4-address [ mask-length ] | ipv6-address [ prefix-length ] } keep-all-routes

Default

Route updates from a peer or peer group are not saved.

Views

BGP IPv4 unicast address family view

BGP-VPN IPv4 unicast address family view

BGP IPv6 unicast address family view

BGP-VPN IPv6 unicast address family view

Predefined user roles

network-admin

Parameters

group-name: Specifies a peer group by its name, a case-sensitive string of 1 to 47 characters. The peer group must have been created.

ipv4-address: Specifies a peer by its IPv4 address. The peer must have been created.

mask-length: Specifies a mask length in the range of 0 to 32. You can use the ipv4-address and mask-length arguments together to specify a subnet. If you specify a subnet, this command saves all route updates from all dynamic peers in the subnet, regardless of whether the routes have passed the configured routing policy.

ipv6-address: Specifies a peer by its IPv6 address. The peer must have been created.

prefix-length: Specifies a prefix length in the range of 0 to 128. You can use the ipv6-address and prefix-length arguments together to specify a subnet. If you specify a subnet, this command saves all route updates from all dynamic peers in the subnet, regardless of whether the routes have passed the configured routing policy.

Usage guidelines

To implement BGP session soft-reset when the local router and a peer or peer group do not support the route refresh feature, use the peer keep-all-routes command. The command saves all route updates received from the peer or peer group. After modifying the route selection policy, filter all saved routes with the new policy to refresh the routing table. This method avoids tearing down BGP sessions.

Examples

# In BGP IPv4 unicast address family view, save all route updates from peer 1.1.1.1.

<Sysname> system-view

[Sysname] bgp 100

[Sysname-bgp-default] address-family ipv4 unicast

[Sysname-bgp-default-ipv4] peer 1.1.1.1 keep-all-routes

Related commands

peer capability-advertise route-refresh

refresh bgp

peer low-memory-exempt

Use peer low-memory-exempt to configure BGP to protect EBGP peers or peer groups when the memory usage reaches level 2 threshold.

Use undo peer low-memory-exempt to remove the configuration.

Syntax

peer { group-name | ipv4-address [ mask-length ] | ipv6-address [ prefix-length ] } low-memory-exempt

undo peer { group-name | ipv4-address [ mask-length ] | ipv6-address [ prefix-length ] } low-memory-exempt

Default

When the memory usage reaches level 2 threshold, BGP tears down an EBGP session to release memory resources periodically.

Views

BGP instance view

BGP-VPN instance view

Predefined user roles

network-admin

Parameters

group-name: Specifies a peer group by its name, a case-sensitive string of 1 to 47 characters. The peer group must have been created.

ipv4-address: Specifies a peer by its IPv4 address. The peer must have been created.

mask-length: Specifies a mask length in the range of 0 to 32. You can use the ipv4-address and mask-length arguments together to specify a subnet. If you specify a subnet in this command, BGP protects all dynamic peers in the subnet when the memory usage reaches level 2 threshold.

ipv6-address: Specifies a peer by its IPv6 address. The peer must have been created.

prefix-length: Specifies a prefix length in the range of 0 to 128. You can use the ipv6-address and prefix-length arguments together to specify a subnet. If you specify a subnet in this command, BGP protects all dynamic peers in the subnet when the memory usage reaches level 2 threshold.

Usage guidelines

When level 2 memory usage threshold is reached, BGP tears down an EBGP session to release memory resources periodically until the memory usage is exempt from level 2 threshold. You can use this command to avoid tearing down the BGP session to an EBGP peer when memory usage reaches level 2 threshold. For more information about thresholds, see Fundamentals Configuration Guide.

Examples

# In BGP instance view, configure BGP to protect EBGP peer 1.1.1.1 when the memory usage reaches level 2 threshold.

<Sysname> system-view

[Sysname] bgp 100

[Sysname-bgp-default] peer 1.1.1.1 as-number 200

[Sysname-bgp-default] peer 1.1.1.1 low-memory-exempt

peer monitor-group

Use peer monitor-group to add a peer or peer group to a peer monitoring group.

Use undo peer monitor-group to remove a peer or peer group from its peer monitoring group.

Syntax

peer { group-name | ipv4-address [ mask-length ] | ipv6-address [ prefix-length ] } monitor-group monitor-group-name

undo peer { group-name | ipv4-address [ mask-length ] | ipv6-address [ prefix-length ] } monitor-group

Default

A peer or peer group does not belong to any peer monitoring group.

Views

BGP instance view

BGP-VPN instance view

Predefined user roles

network-admin

Parameters

group-name: Specifies a BGP peer group by its name, a case-sensitive string of 1 to 47 characters. The specified peer group must have been created.

ipv4-address: Specifies a BGP peer by its IPv4 address. The specified peer group must have been created.

mask-length: Specifies a mask length in the range of 0 to 32. You can use the ipv4-address and mask-length arguments together to specify a subnet. If you specify a subnet, this command adds all dynamic peers in the subnet to the peer monitoring group.

ipv6-address: Specifies a BGP peer by its IPv6 address. The specified peer group must have been created.

prefix-length: Specifies a prefix length in the range of 0 to 128. You can use the ipv6-address and prefix-length arguments together to specify a subnet. If you specify a subnet, this command adds all dynamic peers in the subnet to the peer monitoring group.

monitor-group-name: Specifies a peer monitoring group by its name, a case-sensitive string of 1 to 47 characters. The specified group must have been created.

Usage guidelines

Non-default vSystems do not support this command.

Application scenarios

A peer monitoring group is mainly used in traffic switchover scenarios. For example, when the local device receives multiple BGP routes to the same destination from multiple BGP peers in AS 10 and AS 20, the traffic to that destination can be load shared between AS 10 and AS 20. If multiple BGP peers within AS 10 are disconnected from the local device, the network administrator might perceive a risk in the network status within AS 10 even if there are still running BGP sessions within the AS. The administrator might need to steer all traffic passing through AS 10 to other ASs. You can configure this feature to implement automatic traffic switchover in such scenarios.

Operating mechanism

Execute the monitor-group command to create a peer monitoring group, and then execute the peer monitor-group command to add shared-risk BGP peers to the group. The state of a BGP peer in a peer monitoring group depends on the state of the BGP session between the local device and that peer:

· If the BGP session is in Established state when you add the peer to the peer monitoring group, the peer is in UP state. If the BGP session is not in Established state, the peer is in INIT state.

· If the BGP session state transitions from INIT to Established after you add the peer to the peer monitoring group, the peer state will change to UP.

· If the BGP session state transitions from Established to another state, the peer state will change from UP to DOWN. This rule does not apply to the following scenarios where BGP configurations bring about BGP session state changes:

¡ The BGP session is terminated during a normal GR process. In this situation, the state of the BGP peer does not change in the peer monitoring group.

¡ The BGP session is terminated due to other BGP configurations (for example, the peer ignore command). In this situation, if the number of DOWN-state BGP peers in the peer monitoring group does not reach the specified threshold, the state of the disconnected peer will change to INIT. If the specified threshold is reached, the state of the disconnected peer remains DOWN.

When the number of DOWN-state BGP peers in the peer monitoring group reaches the specified threshold, the local device will disconnect from all BGP peers in the group to avoid potential traffic loss.

Restrictions and guidelines

The number of BGP sessions in a peer monitoring group depends on the number of BGP peers in the group. Each BGP peer is counted as one BGP session, regardless of whether the peer has established sessions in multiple address families. The BGP sessions created by using the same IP address in different BGP-VPN instances and the public instance are considered as different sessions.

A BGP peer or peer group can be added to only one peer monitoring group.

Examples

# In BGP instance view, add peer 1.1.1.1 to peer monitoring group 1.

<Sysname> system-view

[Sysname] bgp 1

[Sysname-bgp-default] peer 1.1.1.1 monitor-group 1

Related commands

display bgp monitor-group

monitor-group threshold

reset monitor-group

peer monitor-link group

Use peer monitor-link group to configure the BGP session state to collaborate with the monitor link downlink interfaces.

Use undo peer monitor-link group to disable the BGP session state from collaborating with the monitor link downlink interfaces.

Syntax

peer { group-name | ipv4-address [ mask-length ] | ipv6-address [ prefix-length ] } monitor-link group group-id

undo peer { group-name | ipv4-address [ mask-length ] | ipv6-address [ prefix-length ] } monitor-link group

Default

The BGP session state does not collaborate with the monitor link downlink interfaces.

Views

BGP instance view

BGP-VPN instance view

Predefined user roles

network-admin

Parameters

group-name: Specifies a peer group by its name, a case-sensitive string of 1 to 47 characters. The peer group must have been created.

ipv4-address: Specifies a peer by its IPv4 address. The peer must have been created.

ipv6-address: Specifies a peer by its IPv6 address. The peer must have been created.

group-id: Specifies a monitor link group by its ID. The value range for the group-id argument is 1 to 16.

Usage guidelines

Operating mechanism

After this command is executed, the BGP session between the local device and a peer or peer group specified by this command will be used as an uplink interface of the specified monitor link group. The uplink interfaces and downlink interfaces in a monitor link group collaborate as follows:

· Uplink interfaces are defined as follows:

¡ In a monitor link group, an interface specified by using the port uplink or port monitor-link group uplink command is considered as an uplink interface.

¡ In a monitor link group, each BGP process specified by using the monitor bgp command is considered as an uplink interface.

¡ In a monitor link group, a BGP session specified by using the peer monitor-link group command is considered as an uplink interface.

If the BGP sessions specified by using the peer monitor-link group command are established in the BGP process specified by using the monitor bgp command, and at least one of these BGP sessions is in Established state, the BGP process is not considered as an uplink interface. If the BGP sessions specified by using the peer monitor-link group command are established in the BGP process specified by using the monitor bgp command, and none of these BGP sessions is in Established state, these BGP sessions are not considered as uplink interfaces, and only the BGP process is considered as an uplink interface.

For example, use the monitor bgp command to specify BGP instances aaa and bbb as two uplink interfaces in a monitor link group, use the peer monitor-link group command in BGP instance aaa to specify two BGP sessions as the uplink interfaces, and do not use the peer monitor-link group command in BGP instance bbb to specify uplink interfaces. In this case, when at least one of the two specified BGP sessions are in Established state, the monitor link group has three uplink interfaces in total, including two BGP sessions and one BGP process without BGP sessions specified. When neither of the two specified BGP sessions is in Established state, the monitor link group has two uplink interfaces in total. One uplink interface is the BGP process with BGP sessions specified but neither of the BGP sessions is in Established state. The other is the BGP process without BGP sessions specified.

· Downlink interfaces are defined as follows: In a monitor link group, an interface specified by using the port downlink or port monitor-link group downlink command is considered as a downlink interface.

· Uplink interfaces and downlink interfaces collaborate as follows:

¡ When the number of uplink interfaces in up state in a monitor link group is lower than the threshold configured by using the uplink up-port-threshold command, the physical state is set to down for all downlink interfaces in the monitor link group. An uplink interface is determined as up or down following these rules:

- For an interface specified by using the port uplink or port monitor-link group uplink command, the uplink interface is considered as up if the interface is physically up, and the uplink interface is considered as down if the interface is physically down.

- For a BGP process specified by using the monitor bgp command, the uplink interface is considered as up when the BGP instance exists and runs normally, and the uplink interface is considered as down when the BGP instance is deleted and the corresponding process exits.

- For a BGP session specified by using the peer monitor-link group command, the uplink interface is considered as up when the BGP session is in Established state, and the uplink interface is considered as down when the BGP session is in any other state.

¡ When the number of uplink interfaces in up state in a monitor link group is greater than or equal to the threshold configured by using the uplink up-port-threshold command, the physical state is set to up for all downlink interfaces in the monitor link group.

Restrictions and guidelines

To prevent BGP session flappings from causing frequent downlink switchovers in a monitor link group, execute the downlink up-delay command in the monitor link group to set the switchover delay for the downlink interfaces in the monitor link group.

For more information about monitor link, see monitor link configuration in High Availability Configuration Guide.

If you execute this command multiple times for the same peer or peer group, the most recent configuration takes effect.

Examples

# In BGP instance view, configure the BGP session between the local device and peer 1.1.1.1 to collaborate with the downlink interfaces of monitor link group 1.

<Sysname> system-view

[Sysname] bgp 100

[Sysname-bgp-default] peer 1.1.1.1 monitor-link group 1

Related commands

downlink up-delay (High Availability Command Reference)

monitor bgp (High Availability Command Reference)

monitor-link group (High Availability Command Reference)

port (High Availability Command Reference)

port monitor-link group (High Availability Command Reference)

peer nexthop-recursive-policy disable

Use peer nexthop-recursive-policy disable to disable route recursion policy control for routes received from the specified peer or peer group.

Use undo peer nexthop-recursive-policy disable to remove the configuration.

Syntax

peer { group-name | ipv4-address [ mask-length ] | ipv6-address [ prefix-length ] } nexthop-recursive-policy disable

undo peer { group-name | ipv4-address [ mask-length ] | ipv6-address [ prefix-length ] } nexthop-recursive-policy disable

Default

The route recursion policy applies to routes received from the specified peer or peer group.

Views

BGP instance view

BGP-VPN instance view

Predefined user roles

network-admin

Parameters

group-name: Specifies a peer group by its name, a case-sensitive string of 1 to 47 characters. The peer group must have been created.

ipv4-address: Specifies a peer by its IPv4 address. The peer must have been created.

ipv6-address: Specifies a peer by its IPv6 address. The peer must have been created.

Usage guidelines

If you configure routing policy-based recursive lookup for BGP routes, this route recursion policy applies to BGP routes learned from all peers. This command allows you to disable route recursion policy control for routes learned from certain peers, for example, direct EBGP peers.

Examples

# In BGP instance view, disable route recursion policy control for routes received from peer 1.1.1.1.

<Sysname> system-view

[Sysname] bgp 100

[Sysname-bgp-default] peer 1.1.1.1 as-number 200

[Sysname-bgp-default] peer 1.1.1.1 nexthop-recursive-policy disable

Related commands

protocol nexthop recursive-lookup

peer password

Use peer password to enable MD5 authentication for a BGP peer or peer group.

Use undo peer password to remove MD5 authentication for a BGP peer or peer group.

Syntax

peer { group-name | ipv4-address [ mask-length ] | ipv6-address [ prefix-length ] } password { cipher | simple } password

undo peer { group-name | ipv4-address [ mask-length ] | ipv6-address [ prefix-length ] } password

Default

MD5 authentication is disabled.

Views

BGP instance view

BGP-VPN instance view

Predefined user roles

network-admin

Parameters

group-name: Specifies a peer group by its name, a case-sensitive string of 1 to 47 characters. The peer group must have been created.

ipv4-address: Specifies a peer by its IPv4 address. The peer must have been created.

mask-length: Specifies a mask length in the range of 0 to 32. You can use the ipv4-address and mask-length arguments together to specify a subnet. If you specify a subnet, this command enables MD5 authentication for all dynamic peers in the subnet.

ipv6-address: Specifies a peer by its IPv6 address. The peer must have been created.

prefix-length: Specifies a prefix length in the range of 0 to 128. You can use the ipv6-address and prefix-length arguments together to specify a subnet. If you specify a subnet, this command enables MD5 authentication for all dynamic peers in the subnet.

cipher: Specifies a password in encrypted form.

simple: Specifies a password in plaintext form. For security purposes, the password specified in plaintext form will be stored in encrypted form.

password: Specifies the password. Its encrypted form is a case-sensitive string of 33 to 137 characters. Its plaintext form is a case-sensitive string of 1 to 80 characters.

Usage guidelines

You can enable MD5 authentication to enhance security using the following methods:

· Perform MD5 authentication when establishing TCP connections. Only the two parties that have the same password configured can establish TCP connections.

· Perform MD5 calculation on TCP segments to avoid modification to the encapsulated BGP packets.

Examples

# In BGP instance view, perform MD5 authentication on the TCP connection between local router 10.1.100.1 and peer router 10.1.100.2. Set the authentication password to aabbcc in plaintext form.

<Sysname> system-view

[Sysname] bgp 100

[Sysname-bgp-default] peer 10.1.100.2 password simple aabbcc

peer reflect-nearby-group

Use peer reflect-nearby-group to specify a peer or peer group as a client of the nearby cluster.

Use undo peer reflect-nearby-group to remove a peer or peer group from the nearby cluster.

Syntax

peer { group-name | ipv4-address [ mask-length ] } reflect-nearby-group

undo peer { group-name | ipv4-address [ mask-length ] } reflect-nearby-group

Default

The nearby cluster does not have any clients.

Views

BGP EVPN address family view

Predefined user roles

network-admin

Parameters

group-name: Specifies a peer group by its name, a case-sensitive string of 1 to 47 characters. The peer group must have been created.

ipv4-address: Specifies a peer by its IPv4 address. The peer must have been created.

mask-length: Specifies a mask length in the range of 0 to 32. You can use the ipv4-address and mask-length arguments together to specify a subnet. If you specify a subnet, this command specifies all dynamic peers in the subnet as clients of the nearby cluster.

Usage guidelines

The RR does not change the next hop of routes reflected to clients in the nearby cluster.

After you specify the RR as the next hop of routes to be reflected, you can execute this command to add a peer or peer group to the nearby cluster. Then, the RR does not change the next hop of routes reflected to the peer or peer group.

To specify the RR as the next hop of routes to be reflected, perform one of the following tasks:

· Execute the reflect change-path-attribute command on the RR to allow the RR to change the attributes of routes to be reflected. Then, execute the peer next-hop-local command to set the local router as the next hop of routes sent to a peer or peer group.

· Execute the reflect change-path-attribute command on the RR to allow the RR to change the attributes of routes to be reflected. Then, use a routing policy to set the RR as the next hop of routes to be reflected.

Examples

# In BGP VPNv4 address family view, specify peer 1.1.1.1 as a client of the nearby cluster.

<Sysname> system-view

[Sysname] bgp 100

[Sysname-bgp-default] address-family vpnv4

[Sysname-bgp-default-vpnv4] peer 1.1.1.1 reflect-nearby-group

peer route-mode

Use peer route-mode enable BGP to send routes exchanged with the specified monitored peer or peer group to the BMP server

Use undo peer route-mode to restore the default.

Syntax

peer { group-name | ipv4-address [ mask-length ] | ipv6-address [ prefix-length ] } route-mode { adj-rib-in { pre-policy | post-policy | both } | adj-rib-out { pre-policy | post-policy | both } } *

undo peer { group-name | ipv4-address [ mask-length ] | ipv6-address [ prefix-length ] } route-mode

Default

BGP determines whether to send routes exchanged with a peer or peer group to the BMP server based on the following configurations:

· Configuration of the route-mode adj-rib-in command in BMP server view.

· Configuration of the route-mode adj-rib-out command in BMP server view.

Views

BGP instance view

BGP-VPN instance view

Predefined user roles

network-admin

Parameters

group-name: Specifies a peer group by its name, a case-sensitive string of 1 to 47 characters. The peer group must have been created.

ipv4-address: Specifies a peer by its IPv4 address. The peer must have been created.

ipv6-address: Specifies a peer by its IPv6 address. The peer must have been created.

adj-rib-in: Sends routes received from the specified monitored peer or peer group to the BMP server.

adj-rib-out: Sends routes advertised to the specified monitored peer and peer group to the BMP server.

pre-policy: Sends routes to the BMP server without route filtering.

post-policy: Sends routes to the BMP server after route filtering.

both: Sends both filtered and unfiltered routes to the BMP server.

Usage guidelines

To enable BGP to send routes exchanged with a peer or peer group to the BMP server, make sure BGP has established a TCP connection to the BMP server.

The configuration of the route-mode adj-rib-in or route-mode adj-rib-out command in BMP server view takes effect on all peers and peer groups. The configuration of the peer route-mode command in BGP instance view or BGP-VPN instance view takes effect only on the specified peer or peer group. The configuration of the peer route-mode command takes precedence over the configuration of the route-mode adj-rib-in or route-mode adj-rib-out command.

If you execute this command multiple times for a peer or peer group, the most recent configuration takes effect.

Examples

# Send routes received from peer 1.1.1.1 to the BMP server without route filtering.

<Sysname> system-view

[Sysname] bgp 100

[Sysname-bgp-default] peer 1.1.1.1 route-mode adj-rib-in pre-policy

peer soo

Use peer soo to configure the Site of Origin (SoO) attribute for a BGP peer or peer group.

Use undo peer soo to remove the configuration.

Syntax

peer { group-name | ipv4-address [ mask-length ] } soo site-of-origin

undo peer { group-name | ipv4-address [ mask-length ] } soo

In BGP IPv4 unicast address family view/BGP-VPN IPv4 unicast address family view:

peer { group-name | ipv4-address [ mask-length ] | ipv6-address [ prefix-length ] } soo site-of-origin

undo peer { group-name | ipv4-address [ mask-length ] | ipv6-address [ prefix-length ] } soo

Default

No SoO attribute is configured for a peer or peer group.

Views

BGP IPv4 unicast address family view

BGP-VPN IPv4 unicast address family view

BGP IPv6 unicast address family view

BGP-VPN IPv6 unicast address family view

Predefined user roles

network-admin

Parameters

group-name: Specifies a peer group by its name, a case-sensitive string of 1 to 47 characters. The peer group must have been created.

ipv4-address: Specifies a peer by its IPv4 address. The peer must have been created.

ipv6-address: Specifies a peer by its IPv6 address. The peer must have been created.

site-of-origin: Specifies the SoO attribute, a string of 3 to 24 characters. The SoO attribute has the following formats:

· 16-bit AS number:32-bit user-defined number. For example, 100:3.

· 32-bit IP address:16-bit user-defined number. For example, 192.168.122.15:1.

· 32-bit AS number:16-bit user-defined number, where the minimum value of the AS number is 65536. For example, 65536:1.

· 32-bit IP address/IPv4 address mask length:16-bit user-defined number. For example, 192.168.122.15/24:1.

· 32-bit AS number in dotted format:16-bit user-defined number. For example, 65535.65535:1.

Usage guidelines

The SoO attribute specifies the site where the route was originated. It prevents advertising a route back to the originating site. If the AS-path attribute is lost, the router can use the SoO attribute to avoid routing loops.

After you configure the SoO attribute for a BGP peer or peer group, BGP adds the SoO attribute into the route updates received from the BGP peer or peer group. Before advertising route updates to the peer or peer group, BGP checks the SoO attribute of the route update against the configured SoO attribute. If they are the same, BGP does not advertise the route updates to the BGP peer or peer group to avoid loops.

If a PE configured with AS number substitution connects to multiple CEs in the same VPN site through different interfaces, routing loops will occur. To avoid routing loops, configure the same SoO attribute for the CEs on the PE.

Examples

# In BGP IPv4 unicast address family view, set the SoO attribute to 100:1 for peer 1.1.1.1.

<Sysname> system-view

[Sysname] bgp 100

[Sysname-bgp-default] address-family ipv4

[Sysname-bgp-default-ipv4] peer 1.1.1.1 soo 100:1

Related commands

peer substitute-as

peer tcp-mss

Use peer tcp-mss to s et the TCP maximum segment size (MSS) for a peer or peer group.

Use undo peer tcp-mss to restore the default.

Syntax

peer { group-name | ipv4-address [ mask-length ] | ipv6-address [ prefix-length ] } tcp-mss mss-value

undo peer { group-name | ipv4-address [ mask-length ] | ipv6-address [ prefix-length ] } tcp-mss

Default

The TCP MSS is not set.

Views

BGP instance view

BGP-VPN instance view

Predefined user roles

network-admin

Parameters

group-name: Specifies a peer group by its name, a case-sensitive string of 1 to 47 characters. The peer group must have been created.

ipv4-address: Specifies a peer by its IPv4 address. The peer must have been created.

mask-length: Specifies a mask length in the range of 0 to 32. If you use the ipv4-address and mask-length arguments together to specify a subnet, this command applies to all dynamic peers in the subnet.

ipv6-address: Specifies a peer by its IPv6 address. The peer must have been created.

prefix-length: Specifies a prefix length in the range of 0 to 128. If you use the ipv6-address and prefix-length arguments together to specify a subnet, this command applies to all dynamic peers in the subnet.

mss-value: Specifies the TCP MSS in bytes. The value range for this argument is 176 to 4096.

Usage guidelines

CAUTION:

This command might cause BGP session re-establishment. Make sure you understand the potential impact before executing this command.

‌

BGP typically establishes a multihop TCP connection with a peer. Multiple intermediate devices might fragment BGP packets due to their MTU settings, resulting in frequent packet encapsulations and decapsulations that reduce forwarding efficiency.

To resolve this issue, you can execute this command to set the TCP MSS for a peer or peer group. TCP segments sent by the source will not be re-fragmented along the path to the destination.

During TCP connection establishment with the peer or peer group specified in the peer tcp-mss command, the minimum of the following MSSs takes effect:

· The MSS calculated according to the IPv4 MTU set by the ip mtu command on the peer-facing interface.

· The MSS set by the tcp mss command for the peer-facing interface.

· The MSS calculated according to the path MTU detected by TCP path MTU discovery (enabled with the tcp path-mtu-discovery command).

· The MSS set by the peer tcp-mss command.

The MSS is calculated by using the following formula:

MSS = path MTU (or interface MTU) – IP header length – TCP header length

For more information about MTU and MSS, see IP performance optimization configuration in Layer 3—IP Services Configuration Guide.

Examples

# Set the TCP MSS to 500 for peer group test.

<Sysname> system-view

[Sysname] bgp 100

[Sysname-bgp-default] peer test tcp-mss 500

Warning:This operation might reset the peer session. Continue? [Y/N]:

Related commands

tcp path-mtu-discovery (Layer 3 —IP Services Command Reference)

peer tracking

Use peer tracking to enable peer unreachability detection.

Use undo peer tracking to disable peer unreachability detection.

Syntax

peer { group-name | ipv4-address [ mask-length ] | ipv6-address [ prefix-length ] } tracking [ delay delay-time ]

undo peer { group-name | ipv4-address [ mask-length ] | ipv6-address [ prefix-length ] } tracking

Default

Peer unreachability detection is disabled.

Views

BGP instance view

BGP-VPN instance view

Predefined user roles

network-admin

Parameters

group-name: Specifies a peer group by its name, a case-sensitive string of 1 to 47 characters. The peer group must have been created.

ipv4-address: Specifies a peer by its IPv4 address. The peer must have been created.

ipv6-address: Specifies a peer by its IPv6 address. The peer must have been created.

delay delay-time: Sets the delay time of peer disconnection in seconds. The value range for the delay-time argument is 0 to 65535. If you do not specify this option, BGP disconnects from the specified peer or peer group immediately when that peer or peer group is detected unreachable.

Usage guidelines

Peer unreachability detection enables BGP to discover link failures quickly. With this feature enabled, BGP will disconnect from the specified peer or peer group if that peer or peer group is detected unreachable.

BGP considers a peer unreachable if one of the following conditions exists:

· BGP cannot find a route to that peer in the routing table of the current public-network instance or VPN instance.

· BGP finds the route to that peer in the routing table of the current public-network instance or VPN instance is a blackhole route.

When you set the delay time of peer disconnection, follow these guidelines to improve network stability:

· To avoid BGP session flappings caused by unstable traffic, make sure the delay time of peer disconnection is longer than the convergence time of IGP routes.

· With peer unreachability detection enabled, the GR helper can detect whether the GR restarter is reachable. To ensure successful GR, make sure the delay time of peer disconnection is longer than the GR timer plus the extra timer to wait.

For more information about the GR timer and the extra timer to wait, see commands "graceful-restart timer restart" and "peer graceful-restart timer restart extra".

This command does not take effect if you specify a link-local address for the ipv6-address argument.

Examples

# Enable peer unreachability detection for peer 1.1.1.1.

<Sysname> system-view

[Sysname] bgp 100

[Sysname-bgp-default] peer 1.1.1.1 as-number 200

[Sysname-bgp-default] peer 1.1.1.1 tracking

pic

Use pic to enable BGP FRR for a BGP address family.

Use undo pic to disable BGP FRR for a BGP address family.

Syntax

pic

undo pic

Default

BGP FRR is disabled.

Views

BGP IPv4 unicast address family view

BGP-VPN IPv4 unicast address family view

BGP IPv6 unicast address family view

BGP-VPN IPv6 unicast address family view

BGP EVPN address family view

Predefined user roles

network-admin

Usage guidelines

FRR is used in a dual-homing network to protect a primary route with a backup route. It uses ARP (for IPv4), ND (for IPv6), or echo-mode BFD (for IPv4) to detect the connectivity of the primary route. When the primary route fails, BGP directs packets to the backup route.

After you enable FRR, BGP calculates a backup route for each BGP route in the address family if there are two or more unequal-cost routes to reach the destination.

You can also configure BGP FRR by using the fast-reroute route-policy command, which takes precedence over the pic command. For more information about routing policies, see Layer 3—IP Routing Configuration Guide.

Use the pic command with caution because it might cause routing loops in specific scenarios.

Examples

# Enable BGP FRR in BGP IPv4 unicast address family view.

<Sysname> system-view

[Sysname] bgp 100

[Sysname-bgp-default] address-family ipv4 unicast

[Sysname-bgp-default-ipv4] pic

Related commands

fast-reroute route-policy

primary-path-detect bfd

Use primary-path-detect bfd to configure BGP FRR to use BFD to detect next hop connectivity for the primary route.

Use undo primary-path-detect bfd to restore the default.

Syntax

primary-path-detect bfd { ctrl | echo }

undo primary-path-detect bfd

Default

BGP FRR uses ARP to detect the connectivity to the next hop of the primary route.

Views

BGP instance view

Predefined user roles

network-admin

Parameters

ctrl: Uses control-mode BFD to detect the connectivity to the next hop of the primary route.

echo: Uses echo-mode BFD to detect the connectivity to the next hop of the primary route.

Usage guidelines

This command enables BGP to create an IP FRR BFD session that detects next hop connectivity for the primary route. This can speed up primary and backup route switchover when the next hop of the primary route fails.

This command takes effect and creates an IP FRR BFD session only when the primary route has a backup next hop.

BGP does not support backup next hop calculation for the routes used for load balancing. This command cannot take effect when the primary route is an equal-cost route. To enable BFD-based next hop detection for equal-cost routes, use the primary-path-detect bfd protocol-ecmp bgp command or the primary-path-detect bfd protocol-ecmp bgp4+ command. For more information about the two commands, see IP routing basics configuration in Layer 3—IP Routing Command Reference.

BGP can establish a control-mode BFD session with a peer only after negotiation. To use control-mode BFD to detect the next hop of the primary link, perform one of the following tasks:

· Execute the primary-path-detect bfd command on the peer device in the primary link.

This task is applicable when both ends of the primary link are configured with FRR.

· Manually configure a static BFD session that uses the following settings on the peer device in the primary link:

¡ Source IP address: Destination IP address of the BFD session automatically created on the local device in the primary link.

¡ Destination IP address: Source IP address of the BFD session automatically created on the local device in the primary link.

¡ Remote ID: Local ID of the BFD session automatically created on the local device in the primary link.

When another routing protocol (such as RIB, OSPF, or IS-IS) uses BFD to detect next hop connectivity for the primary route, it also creates a BFD session. If the detected link is the same as the link attached to the next hop of the BGP primary route, BGP reuses the BFD session created by the protocol. In this situation, BGP will not create an additional BFD session.

If you execute this command multiple times, the most recent configuration takes effect.

Examples

# In BGP instance view, configure BGP FRR to use echo-mode BFD to detect next hop connectivity for the primary route.

<Sysname> system-view

[Sysname] bgp 100

[Sysname-bgp-default] primary-path-detect bfd echo

Related commands

fast-reroute route-policy

pic

primary-path-detect bfd (Layer 3—IP Routing Command Reference)

refresh bgp

Use refresh bgp to manually soft-reset BGP sessions.

Syntax

refresh bgp [ instance instance-name ] { ipv4-address [ mask-length ] | all | external | group group-name | internal } { export | import } ipv4 [ multicast | mvpn | rtfilter | sr-policy | [ unicast ] [ vpn-instance vpn-instance-name ] ]

refresh bgp [ instance instance-name ] ipv6-address [ mask-length ] { export | import } ipv4 [ unicast ] [ vpn-instance vpn-instance-name ]

refresh bgp [ instance instance-name ] { ipv6-address [ prefix-length ] | all | external | group group-name | internal } { export | import } ipv6 [ multicast | sr-policy | [ unicast ] [ vpn-instance vpn-instance-name ] ]

refresh bgp [ instance instance-name ] ipv4-address [ mask-length ] { export | import } ipv6 [ unicast ] [ vpn-instance vpn-instance-name ]

refresh bgp [ instance instance-name ] { ipv4-address [ mask-length ] | ipv6-address [ prefix-length ] | all | external | group group-name | internal } { export | import } link-state

refresh bgp [ instance instance-name ] { ipv4-address [ mask-length ] | all | external | group group-name | internal } { export | import } l2vpn evpn

Views

User view

Predefined user roles

network-admin

Parameters

instance instance-name: Specifies a BGP instance by its name, a case-sensitive string of 1 to 31 characters. If you do not specify this option, the command soft-resets BGP sessions for the default BGP instance.

ipv4-address: Soft-resets the BGP session to a peer specified by its IP address.

mask-length: Specifies a mask length in the range of 0 to 32. You can use the ipv4-address and mask-length arguments together to specify a subnet. If you specify a subnet, this command soft-resets BGP sessions to all dynamic peers in the subnet.

ipv6-address: Soft-resets the BGP session to a peer specified by its IPv6 address.

prefix-length: Specifies a prefix length in the range of 0 to 128. You can use the ipv6-address and prefix-length arguments together to specify a subnet. If you specify a subnet, this command soft-resets BGP sessions to all dynamic peers in the subnet.

all: Soft-resets all BGP sessions.

external: Soft-resets all EBGP sessions.

group group-name: Soft-resets the BGP sessions to the peers of the specified peer group. The group-name argument refers to the name of a peer group, a case-sensitive string of 1 to 47 characters.

internal: Soft-resets all IBGP sessions.

export: Performs outbound soft-reset (filters routes advertised to the specified peer or peer group by using the new configuration).

import: Performs inbound soft-reset (filters routes received from the specified peer or peer group by using the new configuration).

ipv4: Soft-resets BGP sessions for IPv4 address family.

ipv6: Soft-resets BGP sessions for IPv6 address family.

link-state: Soft-resets BGP sessions for LS address family.

mvpn: Soft-resets BGP sessions for IPv4 MVPN address family.

rtfilter: Soft-resets BGP sessions for IPv4 RT filter address family.

sr-policy: Soft-resets BGP sessions for SR policy address family.

unicast: Soft-resets BGP sessions for unicast address family.

l2vpn evpn: Soft-resets BGP sessions for EVPN address family.

vpn-instance vpn-instance-name: Specifies a VPN instance by its name, a case-sensitive string of 1 to 31 characters. If you do not specify a VPN instance, this command soft-resets BGP sessions for the specified address family on the public network.

Usage guidelines

A soft-reset operation enables the router to apply a new route selection policy without tearing down BGP connections.

To apply a new policy to outbound BGP sessions, execute this command with the export keyword. The router uses the new policy to filter routing information and sends the routing information that passes the filtering to the BGP peers.

To apply a new policy to inbound sessions, execute this command with the import keyword. The router advertises a route-refresh message to the peer and the peer resends its routing information to the router. After receiving the routing information, the router uses the new policy to filter the routing information.

This command requires that both the local router and the peer support route refresh.

If the peer keep-all-routes command is configured, the refresh bgp import command does not take effect.

By default, the unicast keyword is used if you do not specify the unicast keyword.

Examples

# Soft-reset all inbound BGP sessions for the IPv4 unicast address family.

<Sysname> refresh bgp all import ipv4

Related commands

peer capability-advertise route-refresh

peer keep-all-routes

reset bgp bmp server statistics

Use reset bgp bmp server statistics to clear BMP server statistics.

Syntax

reset bgp [ instance instance-name ] bmp server server-number statistics

Views

User view

Predefined user roles

network-admin

Parameters

instance instance-name: Specifies a BGP instance by its name, a case-sensitive string of 1 to 31 characters. If you do not specify this option, the command clears the BMP server statistics of the default BGP instance.

server-number: Specifies a BMP server by its number in the range of 1 to 8.

Examples

# Clear the statistics of BMP server 1.

<Sysname> reset bgp bmp server 1 statistics

Related commands

display bgp bmp server

reset monitor-group

Use reset monitor-group to restore the normal sessions in a peer monitoring group.

Syntax

reset bgp [ instance instance-name ] monitor-group monitor-group-name

Views

User view

Predefined user roles

network-admin

Parameters

instance instance-name: Specifies a BGP instance by its name, a case-sensitive string of 1 to 31 characters. If you do not specify this option, the command takes effect on the default BGP instance.

monitor-group-name: Specifies a peer monitoring group by its name, a case-sensitive string of 1 to 47 characters.

Usage guidelines

Application scenarios

With the peer monitoring group feature configured, when the number of DOWN-state BGP peers reaches the specified threshold, the local device disconnects from all peers in the peer monitoring group. The local device will not proactively establish sessions to the devices in the group. To re-establish BGP sessions to the devices in the peer monitoring group, execute the reset monitor-group command.

Operating mechanism

Execute the reset monitor-group command to place the entire peer monitoring group in INIT state. The state of each normal BGP session will be restored to Established in the group, and the state of BGP peers corresponding to those BGP sessions will be restored to UP in the group.

Examples

# Restore the normal sessions in peer monitoring group 1.

<Sysname> reset bgp monitor-group 1

Related commands

display bgp monitor-group

monitor-group threshold

peer monitor-group

route-delete delay

Use route-delete delay to delay BGP in notifying the RIB to delete BGP routes.

Use undo route-delete delay to restore the default.

Syntax

route-delete delay delay-value

undo route-delete delay

Default

The delay timer is 0 seconds. BGP is not delayed in notifying the RIB to delete BGP routes.

Views

BGP IPv4 unicast address family view

BGP-VPN IPv4 unicast address family view

BGP IPv6 unicast address family view

BGP-VPN IPv6 unicast address family view

Predefined user roles

network-admin

Parameters

delay-value: Specifies the delay timer in the range of 0 to 600 seconds. A value of 0 indicates that BGP is not delayed in notifying the RIB to delete BGP routes.

Usage guidelines

Non-default vSystems do not support this command.

Application scenarios

By default, valid optimal BGP routes can guide traffic forwarding only after they are issued from the BGP routing table to the RIB. When a BGP route is deleted from the BGP routing table, BGP also notifies the RIB to delete the related route. Since the route convergence speed varies by device model, traffic disruption might occur in some scenarios if BGP is not delayed in notifying the RIB to delete BGP routes.

Operating mechanism

You can use this command to specify a delay timer. When a route is deleted from the BGP routing table, BGP starts the delay timer. It does not notify the RIB to delete the related route unless the delay timer expires.

Restrictions and guidelines

This command can delay BGP in notifying the RIB to delete a route only if that route has a unique route prefix in the RIB.

You can repeat this command to modify the delay timer and the new delay timer takes effect as follows:

NOTE:

In this chapter, a delayed route is a route for which BGP sends a deletion notification to the RIB after the specified delay timer expires.

· If the new delay timer is non-zero, it does not take effect on the delayed routes.

· If the new delay timer is 0, the RIB will delete the delayed routes immediately.

Examples

# In BGP IPv4 unicast address family view, set a delay timer of 100 seconds to delay BGP in notifying the RIB to delete BGP routes.

<Sysname> system-view

[Sysname] bgp 100

[Sysname-bgp-default] address-family ipv4

[Sysname-bgp-default-ipv4] route-delete delay 100

route-mode adj-rib-in

Use route-mode adj-rib-in to enable BGP to send routes received from all the monitored peers and peer groups to the BMP server.

Use undo route-mode adj-rib-in to restore the default.

Syntax

route-mode adj-rib-in [ pre-policy | post-policy | both ]

undo route-mode adj-rib-in

Default

BGP sends routes received from all the monitored peers and peer groups to the BMP server without route filtering.

Views

BMP server view

Predefined user roles

network-admin

Parameters

pre-policy: Sends routes to the BMP server without route filtering.

post-policy: Sends routes to the BMP server after route filtering.

both: Sends both filtered and unfiltered routes to the BMP server.

Usage guidelines

To enable BGP to send routes received from all monitored peers and peer groups to the BMP server, make sure BGP has established a TCP connection to the BMP server.

If you do not specify any parameters, the command sends routes received from all the monitored peers and peer groups to the BMP server without route filtering.

The configuration of the route-mode adj-rib-in command takes effect on all peers and peer groups. The configuration of the peer route-mode command in BGP instance view or BGP-VPN instance view takes effect only on the specified peer or peer group. The configuration of the peer route-mode command takes precedence over the configuration of the route-mode adj-rib-in command.

If you execute this command multiple times, the most recent configuration takes effect.

Examples

# Enable BGP to send routes received from all the monitored peers and peer groups to the BMP server after route filtering.

<Sysname> system-view

[Sysname] bmp server 5

[Sysname-bmpserver-5] route-mode adj-rib-in post-policy

route-mode adj-rib-out

Use route-mode adj-rib-out to enable BGP to send routes advertised to all the monitored peers and peer groups to the BMP server.

Use undo route-mode adj-rib-out to restore the default.

Syntax

route-mode adj-rib-out [ pre-policy | post-policy | both ]

undo route-mode adj-rib-out

Default

BGP does not send routes advertised to a monitored peer or peer group to the BMP server.

Views

BMP server view

Predefined user roles

network-admin

Parameters

pre-policy: Sends routes to the BMP server without route filtering.

post-policy: Sends routes to the BMP server after route filtering.

both: Sends both filtered and unfiltered routes to the BMP server.

Usage guidelines

To enable BGP to send routes advertised to all monitored peers and peer groups to the BMP server, make sure BGP has established a TCP connection to the BMP server.

If you do not specify any parameters, the command sends routes advertised to all the monitored peers and peer groups to the BMP server after route filtering.

The configuration of the route-mode adj-rib-out command takes effect on all peers and peer groups. The configuration of the peer route-mode command in BGP instance view or BGP-VPN instance view takes effect only on the specified peer or peer group. The configuration of the peer route-mode command takes precedence over the configuration of the route-mode adj-rib-out command.

If you execute this command multiple times, the most recent configuration takes effect.

Examples

# Enable BGP to send routes advertised to all the monitored peers and peer groups to the BMP server without route filtering.

<Sysname> system-view

[Sysname] bmp server 5

[Sysname-bmpserver-5] route-mode adj-rib-out pre-policy

route-mode loc-rib

Use route-mode loc-rib to configure BGP to send the optimal routes in the routing table to the BMP server.

Use undo route-mode loc-rib to restore the default.

Syntax

route-mode loc-rib { vpn-instance-all | vpn-instance vpn-instance-name } { ipv4 [ flowspec | unicast ] | ipv6 [ flowspec | unicast ] }

route-mode loc-rib { ipv4 [ flowspec | unicast ] | ipv6 [ flowspec | unicast ] }

undo route-mode loc-rib { vpn-instance-all | vpn-instance vpn-instance -name } { ipv4 [ flowspec | unicast ] | ipv6 [ flowspec | unicast ] }

undo route-mode loc-rib { ipv4 [ flowspec | unicast ] | ipv6 [ flowspec | unicast ] }

Default

BGP does not send the optimal routes in the routing table to the BMP server.

Views

BMP server view

Predefined user roles

network-admin

Parameters

vpn-instance-all: Sends the routes of all VPN instances to the BMP server.

vpn-instance vpn-instance-name: Specifies an MPLS L3VPN instance by its name, a case-sensitive string of 1 to 31 characters. If you specify an MPLS L3VPN instance, BGP sends the routes of the VPN instance to the BMP server.

ipv4: Sends optimal IPv4 routes to the BMP server.

flowspec: Sends optimal flowspec routes to the BMP server.

unicast: Sends optimal unicast routes to the BMP server.

ipv6: Sends optimal IPv6 routes to the BMP server.

Usage guidelines

Before executing this command, make sure BGP has established a TCP connection to the BMP server.

After you execute this command, BGP sends all routes to the BMP server. If routes update later, BGP sends only the optimal routes to the server.

If you specify neither the vpn-instance-all keyword nor the vpn-instance vpn-instance-name keyword, BGP sends public BGP routes to the BMP server.

If you specify neither the flowspec keyword nor the unicast keyword, BGP sends the optimal unicast routes to the BMP server.

For BGP to send the routes of multiple address families or VPN instances, you can repeat this command with different address families or VPN instances specified. If you execute the command multiple times for the same address family, the most recent configuration takes effect.

After you execute this command with some keywords specified, you can remove the configuration of this command only by executing the undo form of this command with the same keywords specified.

When you repeat this command, follow these restrictions and guidelines:

· You cannot specify the vpn-instance-all keyword after specifying the vpn-instance vpn-instance-name option.

· You cannot specify the vpn-instance vpn-instance-name option after specifying the vpn-instance-all keyword.

Examples

# Configure BGP to send the optimal routes in the routing table to the BMP server.

<Sysname> system-view

[Sysname] bmp server 5

[Sysname-bmpserver-5] route-mode loc-rib

route-select delay

Use route-select delay to configure optimal route selection delay.

Use undo route-select delay to restore the default.

Syntax

route-select delay delay-value

undo route-select delay

Default

The optimal route selection delay timer is 0 seconds, which means optimal route selection is not delayed.

Views

BGP IPv4 unicast address family view

BGP-VPN IPv4 unicast address family view

BGP IPv6 unicast address family view

BGP-VPN IPv6 unicast address family view

BGP EVPN address family view

BGP LS address family view

BGP IPv4 RT-Filter address family view

BGP IPv4 SR policy address family view

Predefined user roles

network-admin

Parameters

delay-value: Specifies the optimal route selection delay timer in the range of 0 to 600 seconds. A value of 0 means optimal route selection is not delayed.

Usage guidelines

To avoid packet loss caused by path switchover, configure this command to delay optimal route selection upon a route change.

Follow these restrictions and guidelines when you configure the command:

· The optimal route selection delay setting applies only when multiple effective routes with the same prefix exist after a route change occurs.

· For routes being delayed for optimal route selection, modifying the optimal route selection delay timer has the following effects:

¡ If you modify the delay timer to a non-zero value, the routes are not affected, and they still use the original delay timer.

¡ If you execute the undo form of the command or modify the delay timer to 0, the device performs optimal route selection immediately.

· If you execute the command multiple times for an address family, the most recent configuration takes effect.

· The optimal route selection delay configuration does not apply to the following conditions:

¡ A route change is caused by execution of a command or by route withdrawal.

¡ After a route change occurs, only one route exists for a specific destination network.

¡ An active/standby process switchover occurs.

¡ A route change occurs among equal-cost routes.

¡ Only the optimal and suboptimal routes exist when FRR is configured.

¡ Optimal route selection is triggered by a redistributed route.

¡ The next hop of the optimal route changes and a route with the same prefix is waiting for the delay timer to expire.

Examples

# In BGP IPv4 unicast address family view, set the optimal route selection delay timer to 100 seconds.

<Sysname> system-view

[Sysname] bgp 65009

[Sysname-bgp-default] address-family ipv4 unicast

[Sysname-bgp-default-ipv4] route-select delay 100

routing-table bgp-rib-only

Use routing-table bgp-rib-only to disable BGP from flushing specific routes to the IP routing table.

Use undo routing-table bgp-rib-only to restore the default.

Syntax

routing-table bgp-rib-only [ all ] [ route-policy route-policy-name ]

undo routing-table bgp-rib-only

Default

BGP flushes the optimal routes to the IP routing table.

Views

BGP IPv4 unicast address family view

BGP IPv6 unicast address family view

BGP-VPN IPv4 unicast address family view

BGP-VPN IPv6 unicast address family view

Predefined user roles

network-admin

Parameters

all: Disables BGP from flushing all routes to the IP routing table, including redistributed routes and routes received from peers and peer groups. If you do not specify this keyword, only the routes received from the specified peer or peer group cannot be flushed to the routing table and BGP still flushes redistributed routes to the routing table.

route-policy route-policy-name: Specifies a routing policy by its name, a case-sensitive string of 1 to 63 characters. If you do not specify a routing policy or the specified routing policy does not exist, BGP does not flush any routes to the routing table. The apply clauses in the specified routing policy do not take effect.

Usage guidelines

This command applies to the following scenarios:

· In an MPLS L3VPN network, all the optimal private BGP routes will be flushed to the routing table of a PE by default. You can execute this command to prevent unnecessary routes from being flushed to the IP routing table and improve the forwarding performance of the PE.

· In a route reflection network, execute this command to disable BGP from flushing specific BGP routes to the IP routing table of the RR. Then, the RR only advertises and receives routes but does not forward service traffic, which saves the system resources of the RR.

This command is mutually exclusive with the advertise-rib-active command.

Examples

# In BGP IPv4 unicast address family view, disable BGP from flushing BGP IPv4 unicast routes matching routing policy policy1 to the routing table.

<Sysname> system-view

[Sysname] bgp 100

[Sysname-bgp-default] address-family ipv4 unicast

[Sysname-bgp-default-ipv4] routing-table bgp-rib-only route-policy policy1

server

Use server to configure an IP address and port number for a BMP server.

Use undo server to remove the configuration.

Syntax

server address { ipv4-address | ipv6-address } port port-number

undo server

Default

No IP address and port number are configured for the BMP server.

Views

BMP server view

Predefined user roles

network-admin

Parameters

ipv4-address: Specifies an IPv4 address for the BMP server.

Ipv6-address: Specifies an IPv6 address for the BMP server.

port-number: Specifies a port number for the BMP server, in the range of 1 to 65535.

Usage guidelines

After you configure an IP address and port number for a BMP server, the BMP client establishes a TCP connection to the BMP server and sends BMP messages to the BMP server.

Examples

# Configure IP address 100.1.1.1 and port number 8888 for BMP server 5.

<Sysname> system-view

[Sysname] bmp server 5

[Sysname-bmpserver-5] server address 100.1.1.1 port 8888

server connect-interface

Use server connect-interface to specify the source interface of TCP connections to the BMP server.

Use undo server connect-interface to restore the default.

Syntax

server connect-interface interface-type interface-number

undo server connect-interface

Default

BGP uses the primary IPv4 address of the output interface in the optimal route to the BMP server as the source address of TCP connections to the BMP server.

Views

BMP server view

Predefined user roles

network-admin

Parameters

interface-type interface-number: Specifies an interface by its type and number.

Usage guidelines

After you configure this command, BGP uses the address of the specified interface to establish TCP connections to the BMP server.

For a BMP server, this command does not take effect if the VPN instance of the specified interface is different from that specified by the server vpn-instance command.

Examples

# Configure Loopback 0 as the source interface of TCP connections to BMP server 5.

<Sysname> system-view

[Sysname] bmp server 5

[Sysname-bmpserver-5] server address 100.1.1.1 port 8888

[Sysname-bmpserver-5] server connect-interface loopback0

Related commands

display bgp bmp server

ip vpn-instance (system view) (MCE Command Reference)

server password

Use server password to specify the authentication mode and key for BGP to establish TCP connections to the BMP server.

Use undo server password to restore the default.

Syntax

server password { keychain keychain-name | md5 { cipher | simple } string }

undo server password

Default

BGP establishes TCP connections to the BMP server without authentication.

Views

BMP server view

Predefined user roles

network-admin

Parameters

keychain: Specifies keychain authentication.

keychain-name: Specifies a keychain by its name, a case-sensitive string of 1 to 63 characters. The keychain must have been created.

md5: Specifies MD5 authentication.

cipher: Specifies a password in encrypted form.

simple: Specifies a password in plaintext form. For security purposes, the password specified in plaintext form will be stored in encrypted form.

string: Specifies the password. Its encrypted form is a case-sensitive string of 33 to 137 characters. Its plaintext form is a case-sensitive string of 1 to 80 characters.

Usage guidelines

Configure this command to secure the TCP connections and packets exchanged with the BMP server.

You cannot repeat the server password command to edit the authentication mode and key. To edit the authentication mode and key, first execute the undo server password command and then the server password command to configure a new authentication mode and key.

Examples

# In BMP server view, use keychain abc to authenticate the TCP connections to the BMP server.

<Sysname> system-view

[Sysname] bmp server 5

[Sysname-bmpserver-5] server password keychain abc

server source-address

Use server source-address to specify the source address of TCP connections to the BMP server.

Use undo server source-address to restore the default.

Syntax

server source-address { ipv4-address | ipv6-address }

undo server source-address

Default

BGP uses the primary IPv4 or IPv6 address of the output interface in the optimal route to the BMP server as the source address of TCP connections to the BMP server.

Views

BMP server view

Predefined user roles

network-admin

Parameters

ipv4-address: Specifies the source IPv4 address of TCP connections to the BMP server.

ipv6-address: Specifies the source IPv6 address of TCP connections to the BMP server.

Usage guidelines

For a BMP server, the following rules apply:

· The configuration of the server source-address command does not take effect if the server source-address and server commands specify different types of IP addresses.

· If you execute both the server source-address and server connect-interface commands, the server source-address command takes effect.

Examples

# Configure IP address 100.1.1.1 and port number 8888 for BMP server 5, and then configure 1.1.1.1 as the source address of TCP connections to BMP server 5.

<Sysname> system-view

[Sysname] bmp server 5

[Sysname-bmpserver-5] server address 100.1.1.1 port 8888

[Sysname-bmpserver-5] server source-address 1.1.1.1

Related commands

display bgp bmp server

server connect-interface

server vpn-instance

Use server vpn-instance to specify a VPN instance for a BMP server.

Use undo server vpn-instance to restore the default.

Syntax

server vpn-instance vpn-instance-name

undo server vpn-instance

Default

No VPN instance is specified for a BMP server. A BMP server belongs to the public network.

Views

BMP server view

Predefined user roles

network-admin

Parameters

vpn-instance-name: Specifies a VPN instance by its name, a case-sensitive string of 1 to 31 characters. The specified VPN instance must be an MPLS L3VPN instance and must have been created.

Usage guidelines

If you delete the MPLS L3VPN instance of a BMP server, BGP disconnects from the BMP server. After you create the VPN instance again, BGP reconnects to the BMP server.

If you execute this command multiple times for a BMP server, the most recent configuration takes effect.

Examples

# Configure IP address 100.1.1.1 and port number 8888 for BMP server 5, and specify VPN instance vpna for BMP server 5.

<Sysname> system-view

[Sysname] bmp server 5

[Sysname-bmpserver-5] server address 100.1.1.1 port 8888

[Sysname-bmpserver-5] server vpn-instance vpna

Related commands

server connect-interface

shutdown process

Use shutdown process to shut down BGP sessions to all peers and peer groups.

Use undo shutdown process to restore the default.

Syntax

shutdown process

undo shutdown process

Default

BGP does not shut down sessions to any peers or peer groups.

Views

BGP instance view

Predefined user roles

network-admin

Usage guidelines

For maintenance purposes, you can execute this command to temporarily disconnect BGP sessions from all peers and peer groups on the device. After maintenance, you can restore the sessions by simply executing the undo form of the command without reconfiguring peer or peer group settings.

This command enables the device to tear down all sessions and clear all routing information.

When you configure the shutdown process command together with the peer ignore or ignore all-peers command, follow these restrictions and guidelines:

· Once BGP shutdown is enabled by the shutdown process command, the device cannot establish BGP sessions with all peers and peer groups.

· To disable BGP session establishment with a peer or peer group if you have disabled BGP shutdown, perform one of the following tasks:

¡ Disable BGP session establishment with that peer or peer group by using the peer ignore command.

¡ Disable BGP session establishment with all peers and peer groups by using the ignore all-peers command.

Examples

# Shut down BGP sessions to all peers and peer groups for BGP instance 100.

<Sysname> system-view

[Sysname] bgp 100

[Sysname-bgp-default] shutdown process

statistics-interval

Use statistics-interval to set the interval at which BGP sends statistics information to the BMP server.

Use undo statistics-interval to restore the default.

Syntax

statistics-interval value

undo statistics-interval

Default

BGP does not send statistics information to the BMP server.

Views

BMP server view

Predefined user roles

network-admin

Parameters

value: Specifies the interval at which BGP sends statistics information to the BMP server, in the range of 1 to 3600 seconds.

Usage guidelines

After establishing a TCP connection to the BMP server, BGP sends statistics information to the BMP server at the specified interval.

Examples

# Set the interval to 5 seconds at which BGP sends statistics information to the BMP server.

<Sysname> system-view

[Sysname] bmp server 5

[Sysname-bmpserver-5] statistics-interval 5

update wait-install

Use update wait-install to enable BGP to perform local-FIB route check before route update advertisement.

Use undo update wait-install to restore the default.

Syntax

update wait-install

undo wait-install

Default

L ocal-FIB route check is disabled for BGP. When BGP sends routes in UPDATE messages, it does not identify whether those routes have been installed into the local FIB.

Views

BGP instance view

BGP IPv4 unicast address family view

BGP-VPN IPv4 unicast address family view

BGP IPv6 unicast address family view

BGP-VPN IPv6 unicast address family view

Predefined user roles

network-admin

Usage guidelines

Application scenarios

This command is applicable to devices with poor route convergence performance. After receiving BGP routes from a device (for example, Device A) with poor route convergence performance, a peer device completes route selection and adds the selected BGP routes to its local FIB. Packet loss might occur if the peer device finishes those tasks before Device A finishes adding the advertised BP routes into the local FIB. To avoid this issue, use this command to enable local-FIB route check for BGP. Before sending routes in UPDATE messages, BGP identifies whether those routes are installed into the local FIB. Only routes in the local FIB can be advertised in UPDATE messages.

R estrictions and guidelines

When you configure this command, follow these restrictions and guidelines:

· In BGP IPv4 unicast address family view, this command only takes effect on BGP IPv4 unicast routes.

· In BGP IPv6 unicast address family view, this command only takes effect on BGP IPv6 unicast routes.

· In BGP-VPN IPv4 unicast address family view, this command only takes effect on the following routes:

¡ BGP-VPN IPv4 unicast routes.

¡ BGP VPNv4 and BGP EVPN routes generated based on BGP-VPN IPv4 unicast routes.

· In BGP-VPN IPv6 unicast address family view, this command only takes effect on the following routes:

¡ BGP-VPN IPv6 unicast routes.

¡ BGP VPNv6 and BGP EVPN routes generated based on BGP-VPN IPv6 unicast routes.

· In BGP instance view, this command only takes effect on the following routes:

¡ BGP IPv4 and IPv6 unicast routes.

¡ BGP-VPN IPv4 and IPv6 unicast routes.

¡ BGP VPNv4, BGP VPNv6, and BGP EVPN routes generated based on BGP-VPN IPv4 and IPv6 unicast routes.

This command does not take effect on the following routes:

· Routes redistributed by the import-route command.

· Routes advertised by the network command.

· Default routes imported by the default-route imported command.

· BGP VPNv4, BGP VPNv6, and BGP EVPN source routes.

· BGP IPv4 multicast routes and BGP IPv6 multicast routes.

This command only takes effect on BGP routes that are generated after the command is executed. To have this command take effect on BGP routes that are generated before the command is executed, use the reset bgp command to reset BGP sessions and re-obtain route information.

If this command is configured in both BGP instance view and an address family view, the address family-specific configuration takes precedence for the related address family.

This command is mutually exclusive with the routing-table bgp-rib-only command.

Examples

# In BGP IPv4 unicast address family view, enable BGP to perform local-FIB route check before route update advertisement.

<Sysname> system-view

[Sysname] bgp 100

[Sysname-bgp-default] address-family ipv4

[Sysname-bgp-default-ipv4] update wait-install

Related commands

routing-table bgp-rib-only

user-move fast-update

Use user-move fast-update to enable fast host route update upon user migration.

Use undo user-move fast-update to disable fast host route update upon user migration.

Syntax

user-move fast-update

undo user-move fast-update

Default

Fast host route update upon user migration is disabled.

Views

BGP IPv4 unicast address family view

BGP IPv6 unicast address family view

Predefined user roles

network-admin

Usage guidelines

An access device does not detect the online state of a client actively or update the host route entries in real time. Traffic forwarding might be affected when a client roams between access devices. To resolve this issue, execute this command to enable fast host route update upon user migration.

Executing this command also enables BGP to advertise the extended community attribute to all peers and peer groups.

Examples

# In BGP IPv4 unicast address family view, enable fast host route update upon user migration.

<Sysname>system-view

[Sysname] bgp 200

[Sysname-bgp-default] address-family ipv4 unicast

[Sysname-bgp-default-ipv4] user-move fast-update

Related commands

peer advertise-ext-community

06-Layer 3—IP Routing Command Reference

fast-reroute route-policy

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