as-path-limit

Function

The as-path-limit command sets the maximum number of AS numbers in the AS_Path attribute.

The undo as-path-limit command restores the default setting.

By default, no limit is configured on the maximum number of AS numbers in the AS_Path attribute, but the maximum number of AS numbers carried in the AS_Path attribute is limited by the BGP message length.

Format

as-path-limit limit

as-path-limit

undo as-path-limit

Parameters

Parameter	Description	Value
limit	Specifies the maximum number of AS numbers in the AS_Path attribute.	The value is an integer ranging from 1 to 2000. The default value is 255. The maximum value of limit for the 2-byte and 4-byte AS number is the same. If limit is not specified, the maximum number of AS numbers in the AS_Path attribute is 255.

Parameter

Description

Value

limit

Specifies the maximum number of AS numbers in the AS_Path attribute.

The value is an integer ranging from 1 to 2000. The default value is 255.

The maximum value of limit for the 2-byte and 4-byte AS number is the same.

If limit is not specified, the maximum number of AS numbers in the AS_Path attribute is 255.

Views

BGP view

Default Level

2: Configuration level

Task Name and Operations

Task Name	Operations
bgp	write

Usage Guidelines

Usage Scenario

This command is used to restrict the maximum number of AS numbers in the AS_Path attribute only when the AS_Path attribute is reconstructed or summarized routes are generated.

Configuration Impact

After the as-path-limit command is configured, the device checks whether the number of AS numbers in the AS_Path attribute of each received or advertised route exceeds the maximum value. If the number of AS numbers exceeds the maximum value, the Router discards the route. Therefore, if the maximum number of AS numbers in the AS_Path attribute is set too small, routes will be lost.

Example

# Set the maximum number of AS numbers in the AS_Path attribute to 200.

<HUAWEI> system-view
[~HUAWEI] bgp 100
[*HUAWEI-bgp] as-path-limit 200