Command Manual - Routing Protocol
Quidway S3500 Series Ethernet Switches
Chapter 4 BGP Configuration Commands
Huawei Technologies Proprietary
4-4
Example
[Quidway-bgp] compare-different-as-med
4.1.4 confederation id
Syntax
confederation id as-number
undo confederation id
View
BGP view
Parameter
as-number:
The ID of BGP AS confederation. It is equal to the AS number which
contains the AS numbers of multiple sub-ASs. The range is 1 to 65535.
Description
Using
confederation id
command, you can configure confederation identifier. Using
undo confederation id
command, you can cancel the BGP confederation specified by
as-number
parameter.
By default, the confederation ID is not configured.
Confederation can be adopted to solve the problem of too many IBGP full connections
in a large AS domain. The solution is, first dividing the AS domain into several smaller
sub-ASs, and each sub-ASs remains full-connected. These sub-ASs form a
confederation. Key BGP attributes of the route, such as next hop, MED, local
preference, are not discarded across each sub-ASs. The sub-ASs still look like a whole
from the point of view of a confederation although these sub-ASs have EBGP relations.
This can assure the integrality of the former AS domain, and ease the problem of too
many connections in the domain
For the related commands, see
confederation nonstandard
,
confederation peer-as
.
Example
# Confederation 9 consists of four sub-ASs, namely, 38, 39, 40 and 41. Here, the peer
10.1.1.1 is an internal member of the AS confederation while the peer 200.1.1.1 is an
external member of the AS confederation. For external members, Confederation 9 is a
unified AS domain.
[Quidway] bgp 41
[Quidway-bgp] confederation id 9
[Quidway-bgp] confederation peer-as 38 39 40
[Quidway-bgp] group Confed38 external
[Quidway-bgp] peer Confed38 as-number 38