static-route timer ldp-sync hold-down

Function

The static-route timer ldp-sync hold-down command sets the time during which a static route remains inactive and waits for the establishment of an LDP session.

The undo static-route timer ldp-sync hold-down command restores the default setting.

By default, the time during which a static route remains inactive and waits for the establishment of an LDP session is 10 seconds.

Format

static-route timer ldp-sync hold-down { timer | infinite }

undo static-route timer ldp-sync hold-down

Parameters

Parameter	Description	Value
timer	Specifies the time during which a static route remains inactive and waits for an LDP session to be established.	The value is an integer ranging from 0 to 65535, in seconds.
infinite	Indicates that the Hold-down timer never expires. A static route becomes active only after an LDP session is established.	-

Views

Interface view

Default Level

2: Configuration level

Usage Guidelines

Usage Scenario

On an MPLS network with primary and backup links, LSRs establish LSPs based on static routes. When the LDP session of the primary link becomes faulty (the fault is not caused by a link failure) or the primary link recovers, configuring synchronization between LDP and static routes minimizes traffic loss during traffic switchover and switchback. After synchronization between LDP and static routes is enabled, and the static-route timer ldp-sync hold-down command is run, the recovered static route becomes temporarily inactive. It waits for the establishment of an LDP session before the Hold-down timer expires, which synchronizes LDP and the static route.

If the Hold-down timer expires, the static route becomes active regardless of whether an LDP session has been established.

If the Hold-down timer is set to 0 seconds, synchronization between LDP and static routes is disabled on an interface.
If the Hold-down timer is set to infinite, the timer never expires. In this case, the static route becomes active and MPLS traffic is switched only after an LDP session is established.

Precautions

The Hold-down timer cannot be set on loopback interfaces, Layer 2 Ethernet interfaces, or null interfaces.

Example

# Set the time during which a static route remains inactive and waits for the establishment of an LDP session to 20 seconds.

<HUAWEI> system-view
[HUAWEI] interface vlanif 100
[HUAWEI-Vlanif100] static-route timer ldp-sync hold-down 20