private-4-byte-as enable (BGP multi-instance view)

Function

The private-4-byte-as enable command enables the 4-byte private AS number function.

The undo private-4-byte-as enable command disables the 4-byte private AS number function.

By default, the 4-byte private AS number function is not enabled, and the device supports 2-byte private AS numbers instead of 4-byte private AS numbers.

Format

private-4-byte-as enable

undo private-4-byte-as [ enable ]

Parameters

None

Views

BGP multi-instance view

Default Level

2: Configuration level

Task Name and Operations

Task Name	Operations
bgp	write

Usage Guidelines

Usage Scenario

Generally, AS numbers range from 1 to 4294967295, including the public, private, and reserved AS numbers. If the private-4-byte-as enable command is not run, private AS numbers range from 64512 to 65534. AS number 65535 is reserved for special use. After the private-4-byte-as enable command is run, the private AS numbers range from 64512 to 65534 and from 4200000000 to 4294967294. 65535 and 4294967295 are reserved for special use.

Public AS numbers can be used over the Internet, whereas private AS numbers cannot be advertised to the Internet. If private AS numbers are advertised to the Internet, routing loops may occur. Therefore, private AS numbers are used only within a routing domain.

Example

# Enable the 4-byte private AS number function.

<HUAWEI> system-view
[~HUAWEI] bgp 100 instance a
[*HUAWEI-bgp-instance-a] private-4-byte-as enable