l2-multicast pw-fast-control

Function

The l2-multicast pw-fast-control command disables or delays the deletion of Layer 2 multicast forwarding entries of PW outbound interfaces when PWs go Down, so that the services can be restored rapidly when the PWs go Up.

The undo l2-multicast pw-fast-control command restores the default configuration.

By default, the device deletes Layer 2 multicast forwarding entries of PW outbound interfaces when PWs go Down.

Format

l2-multicast pw-fast-control [ holdtime interval ]

undo l2-multicast pw-fast-control [ holdtime interval ]

Parameters

Parameter	Description	Value
holdtime interval	Specifies the holdtime for Layer 2 multicast forwarding entries of PW outbound interfaces when PWs go Down.	The value is an integer ranging from 5 to 120, in seconds.

Parameter

Description

Value

holdtime interval

Specifies the holdtime for Layer 2 multicast forwarding entries of PW outbound interfaces when PWs go Down.

The value is an integer ranging from 5 to 120, in seconds.

Views

VSI-AUTO view, VSI-DEFAULT view, VSI-STATIC view

Default Level

2: Configuration level

Task Name and Operations

Task Name	Operations
l2mc	write

Usage Guidelines

Usage Scenario

Generally, all Layer 2 multicast forwarding entries of a PW outbound interface are deleted after the PW goes Down. The services can be restored only after the PW goes Up and the entries are re-created. To ensure that services are not interrupted or are interrupted for less than 50 ms during PW re-establishment, run the l2-multicast pw-fast-control command to disable or delay the deletion of Layer 2 multicast forwarding entries of PW outbound interfaces when PWs go Down.

Precautions

If the holdtime parameter is specified, the device delays the deletion of Layer 2 multicast forwarding entries as follows:

If a Layer 2 multicast forwarding entry is dynamically created, the device deletes it only after holdtime expires, so that the Layer 2 multicast service can be restored rapidly if the corresponding PW goes Up before holdtime expires.
If a Layer 2 multicast forwarding entry is statically configured, the device deletes it only after holdtime expires, so that the Layer 2 multicast service can be restored rapidly if the corresponding PW goes Up before holdtime expires.
If the holdtime parameter is not specified, the device performs the deletion of Layer 2 multicast forwarding entries as follows:
If a Layer 2 multicast forwarding entry is dynamically created, the device does not proactively delete it when the PW goes Down, but waits for the entry to be aged out.
If a Layer 2 multicast forwarding entry is statically configured, the device waits 120s after the PW goes Down. If the PW goes Up within 120s, the device does not delete the entry; otherwise, the device deletes it.

Example

# Set a holdtime of 20s for Layer 2 multicast forwarding entries of PW outbound interfaces when PWs go Down.

<HUAWEI> system-view
[~HUAWEI] mpls
[*HUAWEI-mpls] quit
[*HUAWEI] mpls l2vpn
[*HUAWEI-l2vpn] quit
[*HUAWEI] igmp-snooping enable
[*HUAWEI] vsi v1
[~HUAWEI-vsi-v1] pwsignal ldp
[*HUAWEI-vsi-v1-ldp] vsi-id 1
[*HUAWEI-vsi-v1-ldp] quit
[*HUAWEI-vsi-v1] l2-multicast pw-fast-control holdtime 20