mpls switch-l2vc encapsulation reroute

Function

The mpls switch-l2vc encapsulation reroute command configures the PW switchback policy on the S-PE where the primary and secondary PWs are configured and are determined in master/slave mode. This command is applicable to the VLL FRR mode and the master/slave mode of PW redundancy.

The undo mpls switch-l2vc encapsulation reroute command deletes the PW switchback policy.

By default, in master/slave mode of PW redundancy, the switchback policy is configured as delayed switchback with the delay being 30 seconds.

Format

mpls switch-l2vc ip-address vc-id encapsulation { ethernet | ip-interworking | ip-layer2 | vlan } reroute { delay delay-time | immediately | never }

undo mpls switch-l2vc ip-address vc-id encapsulation { ethernet | ip-interworking | ip-layer2 | vlan } reroute { delay delay-time | immediately | never }

Parameters

Parameter	Description	Value
ip-address	Specifies an LSR ID of the remote device on the PW.	The value is in dotted decimal notation.
vc-id	Specifies the ID of a L2VC.	The value is a decimal integer ranging from 1 to 4294967295.
encapsulation	Indicates the PW encapsulation type.	-
ethernet	This encapsulation type is used when Ethernet packets do not carry VLAN information.	-
ip-interworking	Enables heterogeneous media IP interworking between Huawei devices.	-
ip-layer2	Enables heterogeneous media IP interworking between a Huawei device and a non-Huawei device.	-
vlan	This encapsulation type is used when Ethernet packets carry VLAN information.	-
delay delay-time	Configures delayed switchback and specifies the delay for it.	The value is a decimal integer ranging from 10 to 10800, in seconds.
immediately	Configures immediate switchback.	-
never	Indicates that traffic is not switched back to the primary PW after the primary PW recovers from a fault. Traffic is switched to the primary PW if the secondary PW fails.	-

Views

System view

Default Level

2: Configuration level

Task Name and Operations

Task Name	Operations
l2vpn	write

Usage Guidelines

Usage Scenario

If the primary and secondary MS-PWs on an SPE work in master/slave PW redundancy mode, you can use this command to configure the revertive switching policy. An appropriate switchback delay helps to prevent or reduce packet loss caused by the switchback.

The independent mode supports only immediate switchback.

The revertive switching policies can be classified into three modes: immediate switchback, delayed switchback, and non-revertive. The usage scenarios of these policies are similar to those described in mpls l2vpn reroute. Note the following in real-world situations:

If a network has heavy service traffic, use the delayed switchback policy. Consider device performance and service scale when specifying the switchback delay.
If the bandwidth of a secondary PW is insufficient but that of the primary PW is sufficient, use the immediate switchback policy.
If the bandwidth of a secondary PW is sufficient but that of the primary PW is insufficient, use the non-revertive policy.

Prerequisites

The primary and secondary PWs have been configured on the SPE using the mpls switch-l2vc command.

Configuration Impact

After a revertive switching policy is configured, the switchback will be performed according to the revertive switching policy.

Precautions

The specified IP address is the LSR ID of the remote peer for the single-homing PW.
The specified pwId is the pwId of the single-homing PW.
The encapsulation type is the same as that specified using the mpls switch-l2vc command.

Example

# Configure the switchback policy on the SPE where the primary and secondary PWs are configured and switch traffic back to the primary PW 35 seconds after the primary PW becomes faulty.

<HUAWEI> system-view
[~HUAWEI] mpls
[*HUAWEI-mpls] quit
[*HUAWEI] mpls l2vpn
[*HUAWEI-l2vpn] quit
[*HUAWEI] mpls switch-l2vc 1.1.1.1 1 between 2.2.2.2 2 backup 3.3.3.3 3 encapsulation vlan
[*HUAWEI] mpls switch-l2vc 1.1.1.1 1 encapsulation vlan reroute delay 35