mpls l2vpn reroute

Function

The mpls l2vpn reroute command configures the switchback policy for the primary and secondary PWs in VLL FRR mode or in master/slave mode of PW redundancy.

The undo mpls l2vpn reroute command restores the default switchback policy.

By default, in VLL FRR mode and in master/slave mode of PW redundancy, the switchback policy is configured as delayed switchback.

Format

mpls l2vpn reroute { { delay delayTime | immediately } [ resume resumeTime ] | never }

undo mpls l2vpn reroute

Parameters

Parameter	Description	Value
delay delayTime	Specifies the delay for switching traffic back to the primary PW.	The value is an integer ranging from 10 to 10800, in seconds. The default value is 30.
immediately	Indicates that traffic is switched back to the primary PW without delay.	-
resume resumeTime	Specifies the time after which the peer PE on the secondary PW is notified that the local PE is recovered from the fault. This parameter applies only to the FRR mode.	The value is an integer ranging from 0 to 600, in seconds. The default value is 10.
never	Indicates that after the fault on the primary PW is rectified, traffic is not switched back to the primary PW until the secondary PW becomes faulty.	-

Views

100ge sub-interface view, 100GE interface view, 10GE sub-interface view, 10GE interface view, 200GE sub-interface view, 25GE sub-interface view, 25GE interface view, 400GE Layer 2 sub-interface view, 400GE sub-interface view, 400GE interface view, 40GE sub-interface view, 40GE interface view, 50GE Layer 2 sub-interface view, 50GE sub-interface view, 50GE interface view, Eth-Trunk Layer 2 sub-interface view, Eth-Trunk sub-interface view, Eth-Trunk interface view, GE Layer 2 sub-interface view, GE optical interface view, GE sub-interface view, GE interface view, GE electrical interface view, Global VE sub-interface view, VE sub-interface view, XGE sub-interface view, XGE interface view, Layer 2 sub-interface view

Default Level

2: Configuration level

Task Name and Operations

Task Name	Operations
l2vpn	write

Usage Guidelines

Usage Scenario

The mpls l2vpn reroute command is used to configure the switchback policy only after the primary and secondary PWs are configured in VLL FRR mode or in master/slave mode of PW redundancy. The switchback policy cannot be configured for the independent mode of PW redundancy.

The FRR and master/slave modes support three types of revertive policies:

Immediate switchback: Traffic is immediately switched back to the primary PW, and a fault notification is sent to the remote PE over the secondary PW. This revertive switching policy applies to scenarios in which users hope traffic to be restored as soon as possible.
You can configure in FRR mode, but cannot do so in master/slave mode.
Delayed switchback: Traffic is switched back to the primary PW after the delay time specified in . After the delay time elapses, the local PE of the secondary PW notifies the remote PE of a fault. If is configured in FRR mode, the peer PE of the secondary PW is notified of fault recovery only after elapses.
Non-revertive: Traffic will not be switched back to the primary PW even after the primary PW recovers. Traffic will be switched back to the primary PW only when the secondary PW fails.
In the case of an asymmetric PWE3 FRR networking, where ACs are Ethernet links:
If the remote shutdown function is configured on the interface of a PE that connects a CE, you are not advised to use the immediate switchback policy, because this policy may lead to network flapping and traffic loss. You can use the delayed switchback policy and set to be a value greater than or equal to 30 seconds.
If the Ethernet OAM function is configured on the interface of a PE that connects the PE to a CE, and the switchback policy is configured, the value of cannot be 0 seconds. The value must be greater than or equal to 1 second.
In a scenario where PWs are associated with E-Trunk, only the immediate switchback policy can be used. After a PE receives a switchback notification packet, the PE immediately performs a PW switchback.

Example

# In the case that the PW is associated with the E-Trunk, configure the PW switchback to be performed immediately after the device receives the Notification packet.

<HUAWEI> system-view
[~HUAWEI] mpls
[*HUAWEI-mpls] quit
[*HUAWEI] mpls l2vpn
[*HUAWEI-l2vpn] quit
[*HUAWEI] interface GigabitEthernet 0/1/0
[*HUAWEI-GigabitEthernet0/1/0] mpls l2vc 1.1.1.1 20
[*HUAWEI-GigabitEthernet0/1/0] mpls l2vc 1.1.1.2 21 secondary
[*HUAWEI-GigabitEthernet0/1/0] mpls l2vpn reroute immediately

# Configure the policy of PW switchback. Traffic is switched back to the primary PW 35s after the primary PW recovers from a fault. At the same time, the peer PE on the secondary PW is notified of a fault. After 200s, the peer PE of the secondary PW is notified that the fault is rectified.

<HUAWEI> system-view
[~HUAWEI] mpls
[*HUAWEI-mpls] quit
[*HUAWEI] mpls l2vpn
[*HUAWEI-l2vpn] quit
[*HUAWEI] interface GigabitEthernet 0/1/0
[*HUAWEI-GigabitEthernet0/1/0] mpls l2vc 1.1.1.1 20
[*HUAWEI-GigabitEthernet0/1/0] mpls l2vc 1.1.1.2 21 secondary
[*HUAWEI-GigabitEthernet0/1/0] mpls l2vpn reroute delay 35 resume 200