04-Layer 3-IP Services Command Reference

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05-IP forwarding basics commands
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05-IP forwarding basics commands 82.49 KB

Basic IP forwarding commands

display fib

Use display fib to display FIB entries.

Syntax

display fib [ vpn-instance vpn-instance-name ] [ ip-address [ mask | mask-length ] ]

Views

Any view

Predefined user roles

network-admin

network-operator

Parameters

vpn-instance vpn-instance-name: Specifies an MPLS L3VPN instance by its name, a case-sensitive string of 1 to 31 characters. To display the FIB entries for the public network, do not specify any VPN instance.

ip-address: Displays the FIB entry that matches the specified destination IP address.

mask: Specifies the mask for the IP address.

mask-length: Specifies the mask length for the IP address. The value range is 0 to 32.

Usage guidelines

If you specify an IP address without a mask or mask length, this command displays the longest matching FIB entry.

If you specify an IP address and a mask or mask length, this command displays the exactly matching FIB entry.

Examples

# Display all FIB entries of the public network.

<Sysname> display fib

 

Destination count: 5 FIB entry count: 5

 

Flag:

  U:Usable   G:Gateway   H:Host   B:Blackhole   D:Dynamic   S:Static

  R:Relay     F:FRR

 

Destination/Mask   Nexthop         Flag     OutInterface/Token       Label

0.0.0.0/32         127.0.0.1       UH       InLoop0                  Null

1.1.1.0/24         192.168.126.1   USGF     M-GE0/0/0                Null

127.0.0.0/8        127.0.0.1       U        InLoop0                  Null

127.0.0.0/32       127.0.0.1       UH       InLoop0                  Null

127.0.0.1/32       127.0.0.1       UH       InLoop0                  Null

# Display the FIB entries for VPN vpn1.

<Sysname> display fib vpn-instance vpn1

Destination count: 6 FIB entry count: 6

 

Flag:

  U:Usable   G:Gateway   H:Host   B:Blackhole   D:Dynamic   S:Static

  R:Relay     F:FRR

 

Destination/Mask   Nexthop         Flag     OutInterface/Token      Label

0.0.0.0/32         127.0.0.1       UH       InLoop0                  Null

20.20.20.0/24      20.20.20.25     U        M-GE0/0/0                Null

20.20.20.0/32      20.20.20.25     UBH      M-GE0/0/0                Null

20.20.20.25/32     127.0.0.1       UH       InLoop0                  Null

20.20.20.25/32     20.20.20.25     H        M-GE0/0/0                Null

20.20.20.255/32    20.20.20.25     UBH      M-GE0/0/0                Null

# Display the FIB entries matching the destination IP address 10.2.1.1.

<Sysname> display fib 10.2.1.1

 

Destination count: 1 FIB entry count: 1

 

Flag:

  U:Usable   G:Gateway   H:Host   B:Blackhole   D:Dynamic   S:Static

  R:Relay     F:FRR

 

Destination/Mask   Nexthop         Flag     OutInterface/Token       Label

10.2.1.1/32        127.0.0.1       UH       InLoop0                  Null

Table 1 Command output

Field

Description

Destination count

Total number of destination addresses.

FIB entry count

Total number of FIB entries.

Destination/Mask

Destination address and the mask length.

Nexthop

Next hop address.

Flag

Flags of routes:

·     U—Usable route.

·     G—Gateway route.

·     H—Host route.

·     B—Blackhole route.

·     D—Dynamic route.

·     S—Static route.

·     R—Relay route.

·     F—Fast reroute.

OutInterface/Token

Output interface/LSP index number.

Label

Inner label.

 

forwarding split-horizon

Use forwarding split-horizon to enable split horizon forwarding.

Use undo forwarding split-horizon to disable split horizon forwarding.

Syntax

forwarding split-horizon

undo forwarding split-horizon

Default

Split horizon forwarding is disabled.

Views

System view

Predefined user roles

network-admin

Usage guidelines

This feature prevents IPv4, IPv6, and MPLS packets from being forwarded out of the physical interface on which they were received, avoiding network loops.

Examples

# Enable split horizon forwarding.

<Sysname> system-view

[Sysname] forwarding split-horizon

ip forwarding-table save

Use ip forwarding-table save to save the IP forwarding entries to a file.

Syntax

ip forwarding-table save filename filename

Views

Any view

Predefined user roles

network-admin

Parameters

filename filename: Specifies the name of a file, a string of 1 to 255 characters. For information about the filename argument, see file system management in Fundamentals Configuration Guide.

Usage guidelines

The command automatically creates the file if you specify a nonexistent file. If the file already exists, this command overwrites the file content.

To automatically save the IP forwarding entries periodically, configure a schedule for the device to automatically run the ip forwarding-table save command. For information about scheduling a task, see Fundamentals Configuration Guide.

Examples

# Save the IP forwarding entries to the fib.txt file.

<Sysname> ip forwarding-table save filename fib.txt


Load sharing commands

bandwidth-based-sharing

Use bandwidth-based-sharing to enable IPv4 load sharing based on bandwidth.

Use undo bandwidth-based-sharing to disable IPv4 load sharing based on bandwidth.

Syntax

bandwidth-based-sharing

undo bandwidth-based-sharing

Default

The IPv4 load sharing based on bandwidth is disabled.

Views

System view

Predefined user roles

network-admin

Usage guidelines

This feature load shares flow traffic among multiple output interfaces based on their load percentages. The device calculates the load percentage for each output interface in terms of their expected bandwidths.

Devices that run load sharing protocols, such as Locator/ID Separation Protocol (LISP), implement load sharing based on the ratios defined by these protocols.

This feature is mutually exclusive with the enhanced ECMP mode configured by the ecmp mode enhanced command.

After you enable this feature, the expected bandwidth set by using the bandwidth command on an interface cannot exceed the actual physical bandwidth of the interface.

After you enable this feature, you must set the expected bandwidth for VLAN interfaces to ensure correct bandwidth allocation.

Examples

# Enable IPv4 load sharing based on bandwidth.

<Sysname> system-view

[Sysname] bandwidth-based-sharing

display ip load-sharing mode

Use display ip load-sharing mode to display the load sharing mode in use.

Syntax

display ip load-sharing mode slot slot-number

Views

Any view

Predefined user roles

network-admin

network-operator

Parameters

slot slot-number: Specifies an IRF member device by its member ID. If you do not specify a member device, this command displays the load sharing mode for all member devices.

Examples

# Display the load sharing mode in use.

<Sysname> display ip load-sharing mode slot 1

Load-sharing mode: per-flow

Load-sharing options: dest-ip | src-ip | ip-pro | dest-port | src-port | ingress-port

Load-sharing algorithm: 1

IP tunnel load-sharing mode: outer

Table 2 Command output

Field

Description

Load-sharing mode

Per-flow load sharing.

Load-sharing options

Options configured for load sharing:

·     dest-ip—Identifies flows by packet's destination IP address.

·     src-ip—Identifies flows by packet's source IP address.

·     ip-pro—Identifies flows by packet's IP protocol.

·     dest-port—Identifies flows by packet's destination port number.

·     src-port—Identifies flows by packet's source port number.

·     ingress-port—Identifies flows by packet's ingress port.

Load-sharing algorithm

Algorithm used by load sharing.

IP tunnel load-sharing mode

Load sharing for IP tunnel packets:

·     inner—Identifies flows by inner IP header information.

·     outer—Identifies flows by outer IP header information.

 

Related commands

ip load-sharing mode

display ip load-sharing path

Use display ip load-sharing path to display the load sharing path selected for a flow.

Syntax

display ip load-sharing path ingress-port interface-type interface-number packet-format { ipv4oe dest-ip ip-address [ src-ip ip-address ] | ipv6oe dest-ipv6 ipv6-address [ src-ipv6 ipv6-address ] } [ dest-port port-id | ip-pro protocol-id | src-port port-id ] *

Views

Any view

Predefined user roles

network-admin

network-operator

Parameters

ingress-port interface-type interface-number: Specifies an ingress port by its type and number.

packet-format { ipv4oe dest-ip ip-address [src-ip ip-address ] | ipv6oe dest-ipv6 ipv6-address [ src-ipv6 ipv6-address ] }: Specifies the packet encapsulation format.

ipv4oe: Specifies the format of IPv4 over Ethernet.

dest-ip ip-address: Specifies the destination IPv4 address in dotted decimal notation. If you do not specify this argument, the calculation uses 0.0.0.0 for path selection.

src-ip ip-address: Specifies the source IPv4 address in dotted decimal notation. If you do not specify this argument, the calculation uses 0.0.0.0 for path selection.

ipv6oe: Specifies the format of IPv6 over Ethernet.

dest-ipv6 ipv6-address: Specifies the destination IPv6 address. If you do not specify this option, the calculation uses 0:0:0:0:0:0:0:0 for path selection.

src-ipv6 ipv6-address: Specifies the source IPv6 address. If you do not specify this option, the calculation uses 0:0:0:0:0:0:0:0 for path selection.

dest-port port-id: Specifies a destination port number in the range of 1 to 65535. If you do not specify this option, the calculation uses 0 for path selection.

ip-pro protocol-id: Specifies an IP protocol by its number in the range of 1 to 65535. If you do not specify this option, the calculation uses 0 for path selection.

source-port port-id: Specifies a source port number in the range of 1 to 65535. If you do not specify this option, the calculation uses 0 for path selection.

Usage guidelines

The option settings in this command must match both the options displayed in the display ip load-sharing mode command and the field values in load shared packets. If the option settings do not meet the requirement, the path displayed by this command might be different from the real path for load sharing.

Examples

# Display the load sharing path selected for the flow with the following attributes: ingress port Twenty-FiveGigE 1/0/3, destination IP address 10.110.0.2, source IP address 10.100.0.2, IP protocol number 153, destination port number 2000, source port number 2000.

<Sysname> display ip load-sharing path ingress-port twenty-fivegige 1/0/3 packet-format ipv4oe dest-ip 10.110.0.2 src-ip 10.100.0.2 ip-pro 153 dest-port 2000 src-port 2000

 

Load-sharing algorithm: 0

Load-sharing options: dest-ip | src-ip | ip-pro | dest-port | src-port | ingress-port

Load-sharing parameters:

  Missing configured are set to 0.

  ingress-port: Twenty-FiveGigE1/0/3

  packet-format: IPv4oE

  dest-ip: 10.110.0.2

  src-ip: 10.100.0.2

  ip-pro: 153

  dest-port: 2000

  src-port: 2000

Path selected: 20.0.0.2(interface Twenty-FiveGigE1/0/3)

Table 3 Command output

Field

Description

Load-sharing algorithm

Load sharing algorithm ID.

Load-sharing options

Load sharing options specified by the ip load-sharing mode command.

Load-sharing parameters

Load sharing parameters that you specify for the display ip load-sharing path command.

Missing configured are set to 0.

Values of the unconfigured parameters are set to 0.

ingress-port

Ingress port of the packet.

packet-format

Packet encapsulation format.

dest-ip

Destination IP address of the packet.

src-ip

Source IP address of the packet.

ip-pro

IP protocol number.

dest-port

Destination port number.

src-port:

Source port number.

Path selected

Selected path information, including the IPv4 or IPv6 address of the next hop and the egress port.

 

Related commands

ip load-sharing mode

ip load-sharing local-first enable

Use ip load-sharing local-first enable to enable local-first load sharing.

Use undo ip load-sharing local-first enable to disable local-first load sharing.

Syntax

ip load-sharing local-first enable

undo ip load-sharing local-first enable

Default

Local-first load sharing is enabled.

Views

System view

Predefined user roles

network-admin

Examples

# Enable local-first load sharing.

<Sysname> system-view

[Sysname] ip load-sharing local-first enable

ip load-sharing mode

Use ip load-sharing mode to configure the load sharing mode.

Use undo ip load-sharing mode to restore the default.

Syntax

ip load-sharing mode per-flow [ algorithm algorithm-number [ seed seed-number ] [ shift shift-number ] | [ dest-ip | dest-port | ingress-port | ip-pro | src-ip | src-port ] * | tunnel { inner | outer } ] { global | slot slot-number }

undo ip load-sharing mode { global | slot slot-number }

Default

The device performs per-flow load sharing based on the following criteria: source IP address, destination IP address, source port number, destination port number, IP protocol number, and ingress port.

Views

System view

Predefined user roles

network-admin

Parameters

algorithm algorithm-number: Specifies an algorithm for per-flow load sharing. The value range for the algorithm-number argument is 0 to 13. If you do not specify an algorithm, the default algorithm value is 8.

seed seed-number: Specifies the seed value for the algorithm. The value range is 0 to ffffffff, and the default value is 0.

shift shift-number: Specifies the shift value for the hash algorithm result. The value range is 0 to 15, and the default value is 0.

per-flow: Implements per-flow load sharing.

dest-ip: Identifies flows by destination IP address.

dest-port: Identifies flows by destination port.

ingress-port: Identifies flows by ingress port.

ip-pro: Identifies flows by protocol number.

src-ip: Identifies flows by source IP address.

src-port: Identifies flows by source port.

tunnel { inner | outer }: Performs load sharing for IP tunnel packets. The inner keyword identifies flows by inner IP header information. The outer keyword identifies flows by outer IP header information. If you do not specify this option, the device performs load sharing based on inner IP header information.

global: Configures the load sharing mode globally.

slot slot-number: Specifies an IRF member device by its member ID. If you do not specify a member device, this command configures the load sharing mode for all member devices.

Usage guidelines

If traffic is not load shared well among interfaces, you can use the seed seed-number option and the shift shift-number option to adjust the algorithm result.

Examples

# Configure per-flow load sharing for slot 1.

<Sysname> system-view

[Sysname] ip load-sharing mode per-flow slot 1

ip load-sharing symmetric enable

Use ip load-sharing symmetric enable to enable symmetric load sharing.

Use undo ip load-sharing symmetric enable to disable symmetric load sharing.

Syntax

ip load-sharing symmetric enable

undo ip load-sharing symmetric enable

Default

Symmetric load sharing is disabled.

Views

System view

Predefined user roles

network-admin

Usage guidelines

Symmetric load sharing ensures that bidirectional traffic specific to a particular source and destination address pair flow along the same path.

Before you enable this feature, first execute the ip load-sharing mode command to configure five tuple-based load sharing. The device will perform load sharing based on the source IP address, destination IP address, source port number, destination port number, and IP protocol number. If not doing so, the device will use the default load sharing mode. In this mode, the packet ingress port is included in load sharing calculation and symmetric load sharing does not take effect.

Examples

# Enable symmetric load sharing.

<Sysname> system-view

[Sysname] ip load-sharing symmetric enable