An IP prefix list can contain multiple items that specify prefix ranges. Each destination IP address prefix of a route is compared with these items in ascending order of their index numbers. A prefix matches the IP prefix list if it matches one item in the list.

AS path list

An AS path list matches the AS_PATH attribute of BGP routes. The AS_PATH attribute identifies the ASs through which a route has passed.

For more information about AS path lists, see "Configuring BGP."

Community list

A community list matches the COMMUNITY attribute of BGP routes. The COMMUNITY attribute identifies the community of BGP routes.

For more information about community lists, see "Configuring BGP."

Extended community list

An extended community list matches the extended community attribute (Route-Target for VPN and Site of Origin) of BGP routes.

For more information about extended community lists, see MPLS Configuration Guide.

Routing policy

A routing policy can contain multiple nodes, which are in a logical OR relationship. A node with a smaller number is matched first. A route matches the routing policy if it matches one node (except the node configured with the continue clause) in the routing policy.

Each node has a match mode of permit or deny.

· permit—Specifies the permit match mode for a routing policy node. If a route meets all the if-match clauses of the node, it is handled by the apply clauses of the node. The route is not compared with the next node unless the continue clause is configured. If a route does not meet all the if-match clauses of the node, it is compared with the next node.

· deny—Specifies the deny match mode for a routing policy node. The apply and continue clauses of a deny node are never executed. If a route meets all the if-match clauses of the node, it is denied without being compared with the next node. If a route does not meet all the if-match clauses of the node, it is compared with the next node.

A node can contain a set of if-match, apply, and continue clauses.

· if-match clauses—Specify the match criteria that match the attributes of routes. The if-match clauses of different types are in a logical AND relationship and the if-match clauses of the same type are in a logical OR relationship. A route must meet if-match clauses of all types to match the node.

· apply clauses—Specify the actions to be taken on permitted routes, such as modifying a route attribute.

· continue clause—Specifies the next node. A route that matches the current node (permit node) must match the specified next node in the same routing policy. The continue clause combines the if-match and apply clauses of the two nodes to improve flexibility of the routing policy.

Follow these guidelines when you configure if-match, apply, and continue clauses:

· If you only want to filter routes, do not configure apply clauses.

· If you do not configure any if-match clauses for a permit node, the node will permit all routes.

· Configure a permit node containing no if-match or apply clauses following multiple deny nodes to allow unmatched routes to pass.

Routing policy tasks at a glance

To configure a routing policy, perform the following tasks:

1. (Optional.) Configure filters:

¡ Configuring an IPv4 prefix list

¡ Configuring an IPv6 prefix list

¡ Configuring an AS path list

¡ Configuring a community list

¡ Configuring an extended community list

2. Configuring a routing policy:

a. Creating a routing policy

b. Configuring if-match clauses

c. Configuring apply clauses

d. Configuring the continue clause

Configuring an IPv4 prefix list

Restrictions and guidelines

If all the items are set to deny mode, no routes can pass the IPv4 prefix list. To permit unmatched IPv4 routes, you must configure the permit 0.0.0.0 0 less-equal 32 item following multiple deny items.

If you do not specify the index-number option, the device assigns index numbers according to the configuration order of the IPv4 prefix list items. The index number starts from 10 and increments by 10 for each of the consecutive prefix list items. The IPv4 prefix list items are matched according to their configuration order.

Procedure

1. Enter system view.

system-view

2. Configure an IPv4 prefix list.

ip prefix-list prefix-list-name [ index index-number ] { deny | permit } ip-address mask-length [ greater-equal min-mask-length ] [ less-equal max-mask-length ]

Configuring an IPv6 prefix list

Restrictions and guidelines

If all items are set to deny mode, no routes can pass the IPv6 prefix list. To permit unmatched IPv6 routes, you must configure the permit :: 0 less-equal 128 item following multiple deny items.

If you do not specify this option, the device assigns index numbers according to the configuration order of the IPv6 prefix list items. The index number starts from 10 and increments by 10 for each of the consecutive prefix list items. The IPv6 prefix list items are matched according to their configuration order.

Procedure

1. Enter system view.

system-view

2. Configure an IPv6 prefix list.

ipv6 prefix-list prefix-list-name [ index index-number ] { deny | permit } ipv6-address { inverse inverse-prefix-length | prefix-length [ greater-equal min-prefix-length ] [ less-equal max-prefix-length ] }

Configuring an AS path list

About this task

You can configure multiple items for an AS path list that is identified by a number. The relationship between the items is logical OR. A route matches the AS path list if it matches one item in the list.

Procedure

1. Enter system view.

system-view

2. Configure an AS path list.

ip as-path { as-path-number | as-path-name } { deny | permit } regular-expression

Configuring a community list

About this task

You can configure multiple items for a community list that is identified by a number. The relationship between the items is logical OR. A route matches the community list if it matches one item in the list.

Procedure

1. Enter system view.

system-view

2. Configure a community list.

¡ Configure a basic community list.

ip community-list { basic-comm-list-num | basic basic-comm-list-name } { deny | permit } [ community-number&<1-32> | aa:nn&<1-32> ] [ internet | no-advertise | no-export | no-export-subconfed ] *

¡ Configure an advanced community list.

ip community-list { adv-comm-list-num | advanced adv-comm-list-name } { deny | permit } regular-expression

Configuring an extended community list

About this task

You can configure multiple items for an extended community list that is identified by a number. The relationship between the items is logical OR. A route matches the extended community list if it matches one item in the list.

Procedure

1. Enter system view.

system-view

2. Configure an extended community list.

ip extcommunity-list { ext-comm-list-number | ext-comm-list-name } { deny | permit } { bandwidth link-bandwidth-value | rt route-target | soo site-of-origin }&<1-32>

Configuring a routing policy

Creating a routing policy

About this task

A routing policy must have a minimum of one permit node. If all the nodes are in deny mode, no routes can pass the routing policy.

Procedure

1. Enter system view.

system-view

2. Create a routing policy and a node, and enter routing policy node view.

route-policy route-policy-name { deny | permit } node node-number

Configuring if-match clauses

About this task

You can either specify no if-match clauses or multiple if-match clauses for a routing policy node. If no if-match clause is specified for a permit node, all routes can pass the node. If no if-match clause is specified for a deny node, no routes can pass the node.

Restrictions and guidelines

When you configure if-match clauses, follow these restrictions and guidelines:

· The if-match clauses of a routing policy node have a logical AND relationship. A route must meet all if-match clauses before it can be executed by the apply clauses of the node. If an if-match command exceeds the maximum length, multiple if-match clauses of the same type are generated. These clauses have a logical OR relationship. A route only needs to meet one of them.

· All IPv4 routes match a node if the if-match clauses of the node use only IPv6 ACLs. All IPv6 routes match a node if the if-match clauses of the node use only IPv4 ACLs.

· If the ACL used by an if-match clause does not exist, the clause is always matched. If no rules of the specified ACL are matched or the match rules are inactive, the clause is not matched.

· If the prefix list, community list, or extended community list used by an if-match clause does not exist, the clause is always matched. If no rules of the specified prefix list, community list, or extended community list are matched, the clause is not matched.

Procedure

1. Enter system view.

system-view

2. Enter routing policy node view.

route-policy route-policy-name { deny | permit } node node-number

3. Match routes whose destination, next hop, or source address matches an ACL or prefix list.

IPv4:

if-match ip { address | next-hop | route-source } { acl { ipv4-acl-number | name ipv4-acl-name } | prefix-list prefix-list-name }

IPv6:

if-match ipv6 { address | next-hop | route-source } { acl { ipv6-acl-number | name ipv6-acl-name } | prefix-list prefix-list-name }

By default, no ACL or prefix list match criterion is configured.

The ACL specified in an if-match clause must be a non-VPN ACL.

4. Configure BGP route match criteria.

¡ Match BGP routes whose AS_PATH attribute matches a specified AS path list.

if-match as-path { as-path-number&<1-32> | as-path-name }

¡ Match BGP routes whose COMMUNITY attribute matches a specified community list.

if-match community { { basic-community-list-number | name comm-list-name } [ whole-match ] | adv-community-list-number }&<1-32>

¡ Match BGP routes whose extended community attribute matches a specified extended community list.

if-match extcommunity { ext-comm-list-number | ext-comm-list-name }&<1-32>

¡ Match BGP routes having the specified local preference.

if-match local-preference preference

¡ Match BGP routes with the specified RPKI validation state.

if-match rpki { invalid | not-found | valid }

By default, no BGP route match criteria are configured.

5. Configure route match criteria.

¡ Match routes having the specified cost.

if-match cost cost-value

¡ Match routes having the specified output interface.

if-match interface { interface-type interface-number }&<1-16>

This command is not supported by BGP.

¡ Match routes having MPLS labels.

if-match mpls-label

¡ Match routes having the specified route type.

if-match route-type { bgp-evpn-ad | bgp-evpn-imet | bgp-evpn-ip-prefix | bgp-evpn-mac-ip | external-type1 | external-type1or2 | external-type2 | internal | is-is-level-1 | is-is-level-2 | nssa-external-type1 | nssa-external-type1or2 | nssa-external-type2 } *

¡ Match IGP routes having the specified tag value.

if-match tag tag-value

By default, no route match criteria are configured.

6. Match routes by using a routing policy.

if-match route-policy route-policy-name

By default, no routing policy is specified to match routes.

Configuring apply clauses

1. Enter system view.

system-view

2. Enter routing policy node view.

route-policy route-policy-name { deny | permit } node node-number

3. Configure BGP route attributes.

¡ Set the AS_PATH attribute for BGP routes.

apply as-path as-number&<1-32> [ replace ]

¡ Delete the specified COMMUNITY attribute for BGP routes.

apply comm-list { comm-list-number | comm-list-name } delete

By default, no COMMUNITY attribute is deleted for BGP routes.

¡ Set the specified COMMUNITY attribute for BGP routes.

apply community { none | additive | { community-number&<1-32> | aa:nn&<1-32> | internet | no-advertise | no-export | no-export-subconfed } * [ additive ] }

¡ Set the extended community attribute for BGP routes.

apply extcommunity { bandwidth link-bandwidth-value | { rt route-target }&<1-32> } [ additive ]

¡ Set the color extended community attribute for BGP routes.

apply extcommunity color color [ additive ]

¡ Set the SoO extended community attribute for BGP routes.

apply extcommunity soo site-of-origin&<1-32> [ additive ]

¡ Set a local preference for BGP routes.

apply local-preference preference

¡ Set the ORIGIN attribute for BGP routes.

apply origin { egp as-number | igp | incomplete }

¡ Set a preferred value for BGP routes.

apply preferred-value preferred-value

¡ Set a traffic index for BGP routes.

apply traffic-index { value | clear }

¡ Set the AIGP attribute for BGP routes.

apply aigp { cost-value | igp-cost }

By default, no BGP route attributes are configured.

4. Configure the route cost and cost type.

¡ Set a cost for routes.

apply cost [ + | - ] cost-value

By default, no cost is set for routes.

¡ Set a cost type for routes.

apply cost-type { external | internal | type-1 | type-2 }

By default, no cost type is set for routes.

5. Set the next hop for routes.

IPv4:

apply ip-address next-hop ip-address [ public | vpn-instance vpn-instance-name ]

IPv6:

apply ipv6 next-hop ipv6-address

By default, no next hop is set for routes.

The configuration does not apply to redistributed routes.

6. Configure a gateway address for EVPN IP prefix advertisement routes.

IPv4:

apply gateway-ip { ip-address | origin-nexthop }

IPv6:

apply ipv6 gateway-ip { ipv6-address | origin-nexthop }

By default, no gateway address is configured for EVPN IP prefix advertisement routes.

7. Configure route priorities.

¡ Set an IP precedence for matching routes.

apply ip-precedence { value | clear }

By default, no IP precedence is set.

¡ Set a preference.

apply preference preference

By default, no preference is set.

¡ Set a prefix priority.

apply prefix-priority { critical | high | medium }

By default, the prefix priority is low.

8. Redistribute routes to the specified IS-IS level.

apply isis { level-1 | level-1-2 | level-2 }

By default, routes are not redistributed into the specified IS-IS level.

9. Set MPLS labels.

apply mpls-label

By default, no MPLS label is set.

10. Set a label index value or SID value.

¡ Set a label index value.

apply label-index index-value

By default, no label index value is set.

¡ Set an SID value.

apply label-value label-value

By default, no SID value is set.

11. Set a local QoS ID for matching routes.

apply qos-local-id { local-id-value | clear }

By default, no local QoS ID is set.

12. Set a tag value for IGP routes.

apply tag tag-value

By default, no tag value is set for IGP routes.

13. Set a backup link for fast reroute (FRR).

IPv4:

apply fast-reroute { backup-interface interface-type interface-number [ backup-nexthop ip-address ] | backup-nexthop ip-address }

IPv6:

apply ipv6 fast-reroute { backup-interface interface-type interface-number [ backup-nexthop ipv6-address ] | backup-nexthop ipv6-address }

By default, no backup link is set for FRR.

Configuring the continue clause

Restrictions and guidelines

When you configure the continue clause to combine multiple nodes, follow these restrictions and guidelines:

· If you configure an apply clause that sets different attribute values on all the nodes, the apply clause of the node configured most recently takes effect.

· If you configure the following apply clauses on all the nodes, the apply clause of each node takes effect:

¡ apply as-path without the replace keyword.

¡ apply cost with the + or – keyword.

¡ apply community with the additive keyword.

¡ apply extcommunity with the additive keyword.

· The apply comm-list delete clause configured on the current node cannot delete the community attributes set by the apply community clauses of the preceding nodes.

Procedure

1. Enter system view.

system-view

2. Enter routing policy node view.

route-policy route-policy-name { deny | permit } node node-number

3. Specify the next node to be matched.

continue [ node-number ]

By default, no continue clause is configured.

The specified next node must have a larger number than the current node.

Display and maintenance commands for routing policies

Execute display commands in any view and reset commands in user view.

Task	Command
Display BGP AS path list information.	display ip as-path [ as-path-number \| as-path-name ]
Display BGP community list information.	display ip community-list [ basic-community-list-number \| adv-community-list-number \| name comm-list-name ]
Display BGP extended community list information.	display ip extcommunity-list [ ext-comm-list-number \| ext-comm-list-name ]
Display IPv4 prefix list statistics.	display ip prefix-list [ name prefix-list-name ]
Display IPv6 prefix list statistics.	display ipv6 prefix-list [ name prefix-list-name ]
Display routing policy information.	display route-policy [ name route-policy-name [ node node-number ] ]
Clear BGP AS path list statistics.	reset ip as-path [ as-path-number \| as-path-name ]
Clear IPv4 prefix list statistics.	reset ip prefix-list [ prefix-list-name ]
Clear IPv6 prefix list statistics.	reset ipv6 prefix-list [ prefix-list-name ]

Routing policy configuration examples

Example: Configuring a routing policy for IPv4 route redistribution

Network configuration

As shown in Figure 1, Router B exchanges routing information with Router A by using OSPF and with Router C by using IS-IS.

On Router B, enable route redistribution from IS-IS to OSPF. Use a routing policy to set the cost of route 172.17.1.0/24 to 100 and the tag of route 172.17.2.0/24 to 20.

Figure 1 Network diagram

‌

Procedure

1. Configure IP addresses for interfaces. (Details not shown.)

2. Configure IS-IS:

# Configure Router C.

<RouterC> system-view

[RouterC] isis

[RouterC-isis-1] is-level level-2

[RouterC-isis-1] network-entity 10.0000.0000.0001.00

[RouterC-isis-1] quit

[RouterC] interface hundredgige 1/0/1

[RouterC-HundredGigE1/0/1] isis enable

[RouterC-HundredGigE1/0/1] quit

[RouterC] interface hundredgige 1/0/2

[RouterC-HundredGigE1/0/2] isis enable

[RouterC-HundredGigE1/0/2] quit

[RouterC] interface hundredgige 1/0/3

[RouterC-HundredGigE1/0/3] isis enable

[RouterC-HundredGigE1/0/3] quit

[RouterC] interface hundredgige 1/0/4

[RouterC-HundredGigE1/0/4] isis enable

[RouterC-HundredGigE1/0/4] quit

# Configure Router B.

<RouterB> system-view

[RouterB] isis

[RouterB-isis-1] is-level level-2

[RouterB-isis-1] network-entity 10.0000.0000.0002.00

[RouterB-isis-1] quit

[RouterB] interface hundredgige 1/0/2

[RouterB-HundredGigE1/0/2] isis enable

[RouterB-HundredGigE1/0/2] quit

3. Configure OSPF and route redistribution:

# Configure OSPF on Router A.

<RouterA> system-view

[RouterA] ospf

[RouterA-ospf-1] area 0

[RouterA-ospf-1-area-0.0.0.0] network 192.168.1.0 0.0.0.255

[RouterA-ospf-1-area-0.0.0.0] quit

[RouterA-ospf-1] quit

# On Router B, configure OSPF and enable route redistribution from IS-IS to OSPF.

[RouterB] ospf

[RouterB-ospf-1] area 0

[RouterB-ospf-1-area-0.0.0.0] network 192.168.1.0 0.0.0.255

[RouterB-ospf-1-area-0.0.0.0] quit

[RouterB-ospf-1] import-route isis 1

[RouterB-ospf-1] quit

# Display the OSPF routing table on Router A to view the redistributed routes.

[RouterA] display ospf routing

OSPF Process 1 with Router ID 192.168.1.1

Routing Tables

Routing for Network

Destination Cost Type NextHop AdvRouter Area

192.168.1.0/24 1 Transit 192.168.1.1 192.168.1.1 0.0.0.0

Routing for ASEs

Destination Cost Type Tag NextHop AdvRouter

172.17.1.0/24 1 Type2 1 192.168.1.2 192.168.2.2

172.17.2.0/24 1 Type2 1 192.168.1.2 192.168.2.2

172.17.3.0/24 1 Type2 1 192.168.1.2 192.168.2.2

Total Nets: 4

Intra Area: 1 Inter Area: 0 ASE: 3 NSSA: 0

4. Configure filtering lists on Router B:

# Configure IPv4 basic ACL 2002 to permit route 172.17.2.0/24.

[RouterB] acl basic 2002

[RouterB-acl-ipv4-basic-2002] rule permit source 172.17.2.0 0.0.0.255

[RouterB-acl-ipv4-basic-2002] quit

# Configure IP prefix list prefix-a to permit route 172.17.1.0/24.

[RouterB] ip prefix-list prefix-a index 10 permit 172.17.1.0 24

5. Configure a routing policy on Router B.

[RouterB] route-policy isis2ospf permit node 10

[RouterB-route-policy-isis2ospf-10] if-match ip address prefix-list prefix-a

[RouterB-route-policy-isis2ospf-10] apply cost 100

[RouterB-route-policy-isis2ospf-10] quit

[RouterB] route-policy isis2ospf permit node 20

[RouterB-route-policy-isis2ospf-20] if-match ip address acl 2002

[RouterB-route-policy-isis2ospf-20] apply tag 20

[RouterB-route-policy-isis2ospf-20] quit

[RouterB] route-policy isis2ospf permit node 30

[RouterB-route-policy-isis2ospf-30] quit

6. Apply the routing policy to route redistribution on Router B:

# On Router B, enable route redistribution from IS-IS to OSPF and apply the routing policy.

[RouterB] ospf

[RouterB-ospf-1] import-route isis 1 route-policy isis2ospf

[RouterB-ospf-1] quit

# Display OSPF routing table information on Router A.

[RouterA] display ospf routing

OSPF Process 1 with Router ID 192.168.1.1

Routing Tables

Routing for Network

Destination Cost Type NextHop AdvRouter Area

192.168.1.0/24 1 Transit 192.168.1.1 192.168.1.1 0.0.0.0

Routing for ASEs

Destination Cost Type Tag NextHop AdvRouter

172.17.1.0/24 100 Type2 1 192.168.1.2 192.168.2.2

172.17.2.0/24 1 Type2 20 192.168.1.2 192.168.2.2

172.17.3.0/24 1 Type2 1 192.168.1.2 192.168.2.2

Total Nets: 4

Intra Area: 1 Inter Area: 0 ASE: 3 NSSA: 0

The output shows that the cost of route 172.17.1.0/24 is 100 and the tag of route 172.17.2.0/24 is 20.

Example: Configuring a routing policy for IPv6 route redistribution

Network configuration

As shown in Figure 2:

· Run RIPng on Router A and Router B.

· Configure three static routes on Router A.

· On Router A, apply a routing policy to redistribute static routes 20::/32 and 40::/32 and deny route 30::/32.

Figure 2 Network diagram

‌

Procedure

1. Configure Router A:

# Configure IPv6 addresses for interfaces HundredGigE 1/0/1 and HundredGigE 1/0/2.

<RouterA> system-view

[RouterA] interface hundredgige 1/0/1

[RouterA-HundredGigE1/0/1] ipv6 address 10::1 32

[RouterA-HundredGigE1/0/1] quit

[RouterA] interface hundredgige 1/0/2

[RouterA-HundredGigE1/0/2] ipv6 address 11::1 32

[RouterA-HundredGigE1/0/2] quit

# Enable RIPng on HundredGigE 1/0/1.

[RouterA] interface hundredgige 1/0/1

[RouterA-HundredGigE1/0/1] ripng 1 enable

[RouterA-HundredGigE1/0/1] quit

# Configure three static routes with next hop 11::2, and make sure the static routes are active.

[RouterA] ipv6 route-static 20:: 32 11::2

[RouterA] ipv6 route-static 30:: 32 11::2

[RouterA] ipv6 route-static 40:: 32 11::2

# Configure a routing policy.

[RouterA] ipv6 prefix-list a index 10 permit 30:: 32

[RouterA] route-policy static2ripng deny node 0

[RouterA-route-policy-static2ripng-0] if-match ipv6 address prefix-list a

[RouterA-route-policy-static2ripng-0] quit

[RouterA] route-policy static2ripng permit node 10

[RouterA-route-policy-static2ripng-10] quit

# Enable RIPng and apply routing policy static2ripng to filter redistributed static routes on Router A.

[RouterA] ripng

[RouterA-ripng-1] import-route static route-policy static2ripng

2. Configure Router B:

# Configure the IPv6 address of HundredGigE 1/0/1.

<RouterB> system-view

[RouterB] interface hundredgige 1/0/1

[RouterB-HundredGigE1/0/1] ipv6 address 10::2 32

# Enable RIPng.

[RouterB] ripng

[RouterB-ripng-1] quit

# Enable RIPng on the interface.

[RouterB] interface hundredgige 1/0/1

[RouterB-HundredGigE1/0/1] ripng 1 enable

[RouterB-HundredGigE1/0/1] quit

Verifying the configuration

# Display the RIPng routing table on Router B.

[RouterB] display ripng 1 route

Route Flags: A - Aging, S - Suppressed, G - Garbage-collect

----------------------------------------------------------------

Peer FE80::7D58:0:CA03:1 on HundredGigE1/0/1

Destination 20::/32,

via FE80::7D58:0:CA03:1, cost 1, tag 0, A, 8 secs

Destination 40::/32,

via FE80::7D58:0:CA03:1, cost 1, tag 0, A, 3 secs

Local route

Destination 10::/32,

via ::, cost 0, tag 0, DOF

04-Layer 3-IP Routing Configuration Guide

Configuring routing policies

About routing policies

ACL

IP prefix list

AS path list

Community list

Extended community list

Routing policy

Routing policy tasks at a glance

Restrictions and guidelines

Procedure

Restrictions and guidelines

Procedure

Configuring an AS path list

About this task

Procedure

About this task

Procedure

About this task

Procedure

Configuring a routing policy

Creating a routing policy

About this task

Procedure

Configuring if-match clauses

About this task

Restrictions and guidelines

Procedure

Configuring apply clauses

Configuring the continue clause

Restrictions and guidelines

Procedure

Display and maintenance commands for routing policies

Routing policy configuration examples

Example: Configuring a routing policy for IPv4 route redistribution

Network configuration

Procedure

Example: Configuring a routing policy for IPv6 route redistribution

Network configuration

Procedure

Verifying the configuration

Cloud & AI

InterConnect

Intelligent Terminal Products

Product Support Services

Technical Service Solutions

Resource Center

Policy

Online Help

Become a Partner

Partner Resources

Partner Business Management

Company Information

News & Events

Contact Us