backoff timer

Function

The backoff timer command sets the initial and maximum values for an Exponential backoff timer.

The undo backoff timer command restores the default settings.

By default, the initial value is 15 and the maximum value is 120, in seconds.

Format

backoff timer init max

undo backoff timer

Parameters

Parameter	Description	Value
init	Specifies the initial value of an Exponential backoff timer.	The value is an integer ranging from 5 to 2147483, in seconds.
max	Specifies the maximum value of an Exponential backoff timer.	The value is an integer ranging from 5 to 2147483, in seconds.

Views

MPLS-LDP view

Default Level

2: Configuration level

Usage Guidelines

Usage Scenario

After an LSR fails to process an LDP Initialization message or is informed that the peer LSR rejects the received LDP Initialization message, the LSR starts the Exponential backoff timer and periodically resends an LDP Initialization message to initiate an LDP session before the Exponential backoff timer expires.

When the Exponential backoff timer starts, the active role waits a period of time equal to the initial value of the Exponential backoff timer to attempt to set up an LDP session for the first time. Subsequently, the active role waits a period of time twice as long as the previous one to attempt to set up an LDP session. When the waiting period reaches the maximum value of the Exponential backoff timer, the active role waits a period of time equal to the maximum value of the Exponential backoff timer to attempt to set up an LDP session.

Run the backoff timer command to change the interval at which the active role attempts to set up a session.

By setting the initial value and maximum value for the Exponential backoff timer, you can flexibly control the reestablishment of sessions in different network environments.

When a device is being upgraded, increase the initial and maximum values to set a large interval at which the active role attempts to set up a session.
When a device that is transmitting services is prone to intermittent disconnections, reduce the initial and maximum values to set a small interval at which the active role attempts to set up a session.

The initial value for the Exponential backoff timer cannot be smaller than 15, and the maximum value cannot be smaller than 120.

Prerequisites

MPLS LDP has been enabled globally using the mpls ldp (system view) command.

Precautions

If a session is disconnected after the backoff timer command is run, the device attempts to set up a session based on the set initial and maximum values of the Exponential backoff timer.

Example

# Set the initial value to 20s and the maximum value to 160s for the Exponential backoff timer.

<HUAWEI> system-view
[HUAWEI] mpls ldp
[HUAWEI-mpls-ldp] backoff timer 20 160