3com S7906E Manuel De Montage

 

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Peers added in the group can have different AS numbers.  

 

Follow these steps to configure an eBGP peer group using the third approach: 

Enter system view 

— 

Enter BGP view 

bgp as-number 

— 

Create an eBGP peer group 

group group-name external 

Required 

Add a peer into the group and 
specify its AS number 

peer ip-address group 
group-name as-number 
as-number 

Required 

 

z 

Do not specify any AS number for a peer before adding it into the peer group.  

z 

Peers added in the group can have different AS numbers.  

 

Configuring BGP community can also help simplify routing policy management, and a community has a 

much larger management scope than a peer group by controlling routing policies of multiple BGP 

routers. 

To guarantee the connectivity between iBGP peers, you need to make them fully meshed. But it 

becomes unpractical when there are large numbers of iBGP peers. Configuring route reflectors or 

confederation can solve it. In a large-scale AS, both of them can be used. 

A BGP community is a group of destinations with the same characteristics. It has no geographical 

boundaries and is independent of ASs. 

You can configure a route policy to define which destinations belong to a BGP community and then 

advertise the community attribute to a peer/peer group. 

You can apply a route policy to filter routes advertised to/received from a peer/peer group according to 

the community attribute. This way helps simplify policy configuration and management. 

For how to configure a route policy, refer to Route Policy Configuration in the IP Routing Volume. 

Follow these steps to configure BGP community: 

Enter system view 

— 

Enter BGP view 

bgp as-number 

—