H3C S7500 Series Ethernet Switches Command Manual

Table Of Contents
Command Manual – Routing Protocol
H3C S7500 Series Ethernet Switches Chapter 5 BGP Configuration Commands
5-5
5.1.5 confederation id
Syntax
confederation id as-number
undo confederation id
View
BGP view
Parameters
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
Use the confederation id command to configure confederation identifier.
Use the undo confederation id command to cancel the BGP confederation specified
by the as-number argument.
By default, no confederation ID is configured.
Confederation can be adopted to solve the problem of too many IBGP fully-meshed
connections in a large AS domain. The solution is by first dividing the AS domain into
several smaller sub-ASs, and each sub-ASs remains fully-meshed. These sub-ASs
form a confederation. Key BGP attributes of the route, such as next hop, MED, and
local preference, are not discarded across each sub-ASs. The sub-ASs still look
integral 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
Related commands: confederation nonstandard, confederation peer-as.
Examples
# 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.
<H3C> system-view
System View: return to User View with Ctrl+Z.
[H3C] bgp 41
[H3C-bgp] confederation id 9
[H3C-bgp] confederation peer-as 38 39 40
[H3C-bgp] group Confed38 external
[H3C-bgp] peer Confed38 as-number 38
[H3C-bgp] peer 10.1.1.1 group Confed 38