BGP - using peer-groups with multiple outbound policies
When implementing BGP, one can use BGP peer groups to simplify the configuration of a large number of BGP peers that share the same configuration. This simplifies configuration and reduces the required CPU processing power since the same update is created once and shared with multiple neighbors.
However, how do peer groups operate if we apply different outbound policies to different neighbors?
All members of a peer group must share identical outbound announcement policies (such as distribute-list, filter-list, and route-map), except for default-originate, which is handled on a per-peer basis even for peer group members.
If you attempt to apply a different policy to different BGP peers that belong to the same peer group, you will get an error message similar to the following:
% Invalid command for a peer-group memeber
However, inbound update policies can be customized for any member of a peer group.
Links:
https://forum.networklessons.com/t/bgp-peer-groups-on-cisco-ios/1237/58?u=lagapidis