mpls ldp timer keepalive-hold

Function

The mpls ldp timer keepalive-hold command sets the Keepalive hold timer value.

The undo mpls ldp timer keepalive-hold command restores the default configuration.

By default, the value of the Keepalive hold timer is 45s.

Format

mpls ldp timer keepalive-hold interval

undo mpls ldp timer keepalive-hold

Parameters

Parameter	Description	Value
interval	Specifies the Keepalive hold timer value.	The value is an integer ranging from 30 to 65535, in seconds.

Parameter

Description

Value

interval

Specifies the Keepalive hold timer value.

The value is an integer ranging from 30 to 65535, in seconds.

Views

Remote MPLS LDP peer view

Default Level

2: Configuration level

Task Name and Operations

Task Name	Operations
mpls-ldp	write

Usage Guidelines

Usage Scenario

LDP peers maintain LDP sessions using LDP PDUs transmitted over session connections. If a node does not receive any LDP PDU before the Keepalive hold timer times out, the node terminates the session by closing the connection.

The default timer value is recommended. On a network where the link status is unstable, you can increase the Keepalive hold timer value properly. This helps prevent LDP flapping.

There are two types of Keepalive hold timers:

Keepalive hold timer of the local session: is used to maintain the local LDP session. You can run the mpls ldp timer keepalive-hold command in the interface view to set the timer value.
Keepalive hold timer of the remote session: is used to maintain the remote LDP session. You can run the mpls ldp timer keepalive-hold command in the remote MPLS LDP peer view to set the timer value.
NOTE:
The timer value that takes effect is the smaller one of the Keepalive hold timer values configured on both ends of an LDP session.

Prerequisites

The remote LDP peer has been configured.

Implementation Procedure

After the mpls ldp timer keepalive-hold command is run, the system displays the following message:

Warning: All the related sessions will be deleted if the operation is performed. Continue? [Y/N]:y

To confirm to run the command, enter y.

Configuration Impact

After the mpls ldp timer keepalive-hold command is run, the Keepalive hold timer value that takes effect is the smaller one of the Keepalive hold timer values configured on both ends of an LDP session.

Precautions

For a local LDP multi-link session, the values of the Keepalive hold timers configured for all links must be the same. If the values are different, the LDP session or LSP cannot be established.

For a coexistent local and remote LDP session, the values of the Keepalive hold timers configured for all links and remote peers must be the same. Otherwise, the LDP session or LSP cannot be established.

If the Keepalive hold timers configured on multiple links and remote peers are different, LDP establishes a session only by using the first-discovered adjacency. Other adjacencies with different configurations cannot be bound to the session. As a result, no LSP can be established on these adjacencies.

If the value of the Keepalive hold timer negotiated by both ends of an LDP session is less than 9s, the value 9s is used.

Note:

Changing the value of a KeepAlive hold timer may lead to reestablishment of related LDP sessions.

Example

# Set the Keepalive hold timer value of the remote session to 40s.

<HUAWEI> system-view
[~HUAWEI] mpls
[*HUAWEI-mpls] mpls ldp
[*HUAWEI-mpls-ldp] quit
[*HUAWEI] mpls ldp remote-peer bji
[*HUAWEI-mpls-ldp-remote-bji] mpls ldp timer keepalive-hold 40