3com S7906E Guide De Référence

 

1-7 

# 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-vpn1] compare-different-as-med 

confederation id as-number 

undo confederation id 

BGP view 

2: System level 

as-number: Number of the AS that contains multiple sub-ASs, in the range 1 to 65535. 

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 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. 

Related commands: confederation nonstandard and confederation peer-as. 

# Confederation 9 consists of four sub-ASs, namely, 38, 39, 40 and 41. The peer 10.1.1.1 is a member 

of the confederation while 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