R3102-R3103-HP 6600/HSR6600 Routers Layer 3 - IP Routing Command Reference

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Examples
# In BGP view, enable the comparison of 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 the comparison of 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-ipv4-vpn1] compare-different-as-med
confederation id
Use confederation id to configure a confederation ID.
Use undo confederation id to remove a specified confederation.
Syntax
confederation id as-number
undo confederation id
Default
No confederation ID is configured.
Views
BGP view
Default command level
2: System level
Parameters
as-number: Specifies the number of the AS that contains multiple sub-ASs, in the range of 1 to
4294967295.
Usage guidelines
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, or local preference, are not discarded when crossing
each sub-AS. The sub-ASs still look like a whole from the perspective of other ASs. This can ensure the
integrity of the former AS, and solve the problem of too many IBGP connections in the AS.
Examples
# Confederation 9 consists of four sub-ASs numbered 38, 39, 40 and 41. The peer 10.1.1.1 is a member
of the confederation and the peer 200.1.1.1 is outside of the confederation. Take sub AS 41 as an
example.
<Sysname> system-view
[Sysname] bgp 41
[Sysname-bgp] confederation id 9
[Sysname-bgp] confederation peer-as 38 39 40
[Sysname-bgp] group Confed38 external