configure bgp add confederation-peer sub-AS-number

configure bgp add confederation-peer sub-AS-number number

Description

Adds a sub-AS to a confederation.

Syntax Description

number Specifies a sub-AS number of the confederation. The range is 1 to 4294967295.

Default

N/A.

Usage Guidelines

Before you can add a sub-AS to a confederation on the switch, you must disable any BGP (Border Gateway Protocol) neighbor sessions that are configured with the same AS number as a remote AS number. To disable BGP neighbor sessions, use the following command:

disable bgp neighbor [remoteaddr | all]

Invoke the configure bgp add confederation-peer sub-AS-number command multiple times to add multiple sub-ASs.

IBGP requires networks to use a fully-meshed router configuration. This requirement does not scale well, especially when BGP is used as an interior gateway protocol. One way to reduce the size of a fully-meshed AS is to divide the AS into multiple sub-autonomous systems and group them into a routing confederation. Within the confederation, all BGP speakers in each sub-AS must be fully-meshed. The confederation is advertised to other networks as a single AS.

The AS number is a 4-byte AS number in either the ASPLAIN or the ASDOT format as described in RFC 5396, Textual Representation of Autonomous System (AS) Numbers.

Example

The following example adds one sub-AS to a confederation using the ASPLAIN 4-byte AS number format:

configure bgp add confederation-peer sub-AS-number 65536

The following example adds one sub-AS to a confederation using the ASDOT 4-byte AS number format:

configure bgp add confederation-peer sub-AS-number 1.15

History

This command was first available in ExtremeXOS 10.1.

This command required a specific license in ExtremeXOS 11.1.

Support for 4-byte AS numbers was first available in ExtremeXOS 12.4.

Platform Availability

This command is available on platforms that support the appropriate license. For complete information about software licensing, including how to obtain and upgrade your license and which licenses support the BGP feature,see the ExtremeXOS 22.2 Feature License Requirements document.