The AS_Path attribute records all the ASs that a route passes through from the source to the destination in the vector order. You can configure the AS_Path attribute to implement flexible route selection.
Apply a Routing Policy to Routes Advertised
The set protocols bgp neighbor route-map command applies a route map to incoming or outgoing routes. It can be used to configure the route map for modifying the AS_Path attribute of the route.
admin@XorPlus# set protocols bgp ipv4 unicast neighbor 2.2.2.2 in route-map map1 admin@XorPlus# commit
Configure an AS Path List to Advertise or Receive Routes from Peers
The set protocols bgp neighbor filter-list command configures an AS Path list to advertise or receive routes from peers.
admin@XorPlus# set protocols bgp ipv4 unicast neighbor 2.2.2.2 in filter-list List1 admin@XorPlus# commit
Configure BGP to Treat two BGP Routes as Equal Cost ven if AS-paths Differ
he set protocols bgp bestpath as-path multipath-relax command configures Border Gateway Protocol (BGP) to treat two BGP routes as equal cost even if their AS-paths differ, as long as their AS-path lengths and other relevant attributes are the same. This allows routes with different AS-paths to be programmed into the forwarding table as equal cost multipath routes. Any changes in BGP configuration are applied by restarting the current BGP sessions on the VRFs.
admin@XorPlus# set protocols bgp bestpath as-path multipath-relax admin@XorPlus# commit