Hi, Today, we noticed a difference in the order that communities were added between 1.6.3 and 1.4.5 version. All exported routes pass through a function, which adds three communities: function match_route_north() { bgp_community.add((64813,lookup_live_id(net.ip))); bgp_community.add(DC_ID); bgp_community.add((64813,lookup_fabric_id(net.ip))); return (net ~ ACAST_PS_ADVERTISE && net ~ ANYCAST_NETWORKS_NORTH && !(net ~ ACAST_PS_DISABLED)); } As you see we add first live_id (which is always 1000) and last the fabric_id(which is always 3). With bird 1.6.3 version we see that live_id community is listed 1st: 1.17.1.143/32 dev lo [direct1 2017-06-07 15:30:29 1496842229] * (240) Type: device unicast univ BGP.origin: IGP BGP.as_path: 61115 BGP.next_hop: 10.1.9.1 BGP.local_pref: 0 BGP.community: (64813,1000) (64815,100) (64813,3) but with 1.4.5 version is listed as last: 1.17.16.143/32 dev lo [direct1 2017-03-10 11:24:36 1489141476] * (240) Type: device unicast univ BGP.origin: IGP BGP.as_path: 6115 BGP.next_hop: 10.1.6.1 BGP.local_pref: 0 BGP.community: (64813,3) (61115,100) (64813,1000) Does anyone know why ? Cheers, Pavlos