The access-group assigned on the interface and the route-map assigned to the BGP neighbor have different functionality and each will do the function that you have assigned through them.
The access-group assigns access list AAA to filter data traffic that is inbound on interface FastEth0/0 and all traffic coming in on that interface must be evaluated by the access list.
The route map assigned to the BGP neighbor will evaluate routes advertised by the neighbor and routes that are advertised and permitted by the route map will be placed into the BGP tables.
The outcome of the configuration as you have posted it would be this:
- the route map uses access list xxx which permits all routes that are advertised from this neighbor.
- the access list on the interface permits only traffic from source address 23.0.0.1.
- since the BGP neighbor is reached through interface FastEth0/0 the BGP packets received from that neighbor are evaluated by access list AAA and are not permitted.
- since no BGP traffic from the neighbor is permitted the BGP neighbor relationship will not be completed and no routes will be learned from that neighbor.
HTH
Rick
HTH
Rick