timer ldp-sync hold-max-cost (IS-IS view)

Function

The timer ldp-sync hold-max-cost command sets the period of time during which an interface in an IS-IS process waits to leave the LDP-IGP synchronization state.

The undo timer ldp-sync hold-max-cost command restores the default period.

By default, IS-IS keeps advertising the maximum cost by sending link state PDUs on a device before an LDP session and an LDP adjacency are reestablished.

Format

timer ldp-sync hold-max-cost infinite

timer ldp-sync hold-max-cost interval

undo timer ldp-sync hold-max-cost

Parameters

Parameter	Description	Value
interval	Specifies the period during which IS-IS sends link state PDUs to advertise the maximum cost on a device.	The value is an integer ranging from 0 to 65535, in seconds.
infinite	Indicates that IS-IS keeps advertising the maximum cost by sending link state PDUs on a device before an LDP session and an LDP adjacency are reestablished.	-

Parameter

Description

Value

interval

Specifies the period during which IS-IS sends link state PDUs to advertise the maximum cost on a device.

The value is an integer ranging from 0 to 65535, in seconds.

infinite

Indicates that IS-IS keeps advertising the maximum cost by sending link state PDUs on a device before an LDP session and an LDP adjacency are reestablished.

Views

IS-IS view

Default Level

2: Configuration level

Task Name and Operations

Task Name	Operations
isis	write

Usage Guidelines

Usage Scenario

LDP-IGP synchronization prevents traffic loss on a network with both primary and backup link switched paths (LSPs). The

timer ldp-sync hold-max-cost command is used in either of the following situations:

When the primary LSP is recovering, this command allows the backup LSP to transmit traffic before the primary LSP is established.
After an LDP session or LDP adjacency fails over the primary LSP, this command is used to allow the backup LSP to transmit traffic before the primary LSP recovers.
Configuring infinite keeps traffic traveling through the backup LSP before the primary LSP is established.

Configuration Impact

If an LDP session or LDP adjacency is unable to go Up, configuring infinite affects IS-IS route selection because the interface keeps advertising the maximum cost.

Example

# Allow IS-IS to keep advertising the maximum cost by sending link state PDUs until the LDP session and an LDP adjacency are reestablished.

<HUAWEI> system-view
[~HUAWEI] isis 100
[*HUAWEI-isis-100] timer ldp-sync hold-max-cost infinite