Confederation Id - H3C S9500 Series Command Manual

Command Manual – BGP
H3C S9500 Series Routing Switches
If there are several paths for one destination available, the path with the smallest MED
is selected.
Do not use this command unless associated ASs adopt the same IGP protocol and
routing selection method.
Examples
# In BGP view, enable to compare the MED for paths from peers in different ASs.
<Sysname> system-view
[Sysname] bgp 100
[Sysname-bgp] compare-different-as-med
# In BGP-VPN instance view, enable to compare the MED for paths from peers in
different ASs (The VPN has been created).
<Sysname> system-view
[Sysname] bgp 100
[Sysname-bgp] ipv4-family vpn-instance vpn1
[Sysname-bgp-vpn1] compare-different-as-med

1.1.8 confederation id

Syntax
confederation id as-number
undo confederation id
View
BGP view
Default Level
2: System level
Parameters
as-number: Number of the AS that contains multiple sub-ASs.
Description
Use the confederation id command to configure a confederation ID.
Use the undo confederation id command to remove a specified confederation.
By default, no confederation ID is configured.
Configuring a confederation can reduce IBGP connections in a large AS. You can split
the AS into several sub-ASs, and each sub-AS remains fully meshed. These sub-ASs
form a confederation. Key IGP attributes of a route, such as the next hop, MED, local
preference, are not discarded when crossing each sub-AS. The sub-ASs still look like a
Chapter 1 BGP Configuration Commands
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