tcp timer pathmtu-age

Function

The tcp timer pathmtu-age command sets the aging time for a TCP PMTU.

The undo tcp timer pathmtu-age command restores the default aging time for a TCP PMTU.

By default, an IPv4 PMTU does not age.

Format

tcp timer pathmtu-age agetime

undo tcp timer pathmtu-age

Parameters

Parameter	Description	Value
agetime	Specifies the aging time of a TCP PMTU.	The value is an integer ranging from 10 to 100, in minutes.

Parameter

Description

Value

agetime

Specifies the aging time of a TCP PMTU.

The value is an integer ranging from 10 to 100, in minutes.

Views

System view

Default Level

2: Configuration level

Task Name and Operations

Task Name	Operations
ip-stack	write

Usage Guidelines

Usage Scenario

If a TCP path MTU option is set, the TCP connection detects the MTU of the forwarding path and send packets according to the MTU. You can configure an aging time for the TCP path MTU so that the TCP connection redetects the MTU after the aging time expires. If no aging time is configured, the detected TCP path MTU never ages.

Configuration Impact

Running the tcp timer pathmtu-age command changes the aging time of dynamic PMTUs only, not static PMTUs. Static PMTUs never age.

Precautions

A PMTU needs to be set based on the real world situation, such as network stability. The default PMTU is recommended. That is, a PMTU does not age.

If the aging time of a PMTU is set to be too longer, the PMTU may not be updated in time. This will affect network performance.
If the aging time of a PMTU is set to be too short, data transmission efficiency on the network will be affected.

Example

# Set the aging time of a TCP PMTU to 50 minutes.

<HUAWEI> system-view
[*HUAWEI] tcp timer pathmtu-age 50