After update bird not announce prefixes with the same filter in config filter AS8905_out { if ( source = RTS_STATIC_DEVICE && net = 91.211.216.0/22 ) then { bgp_community = add(bgp_community,(8905,1050)); #backup community bgp_origin = 0; bgp_path.prepend(48720); bgp_path.prepend(48720); bgp_path.prepend(48720); bgp_path.prepend(48720); accept; } if ( source = RTS_STATIC_DEVICE && net = 193.9.244.0/22 ) then { bgp_community = add(bgp_community,(8905,1050)); #backup community bgp_origin = 0; bgp_path.prepend(48720); bgp_path.prepend(48720); bgp_path.prepend(48720); bgp_path.prepend(48720); accept; } if ( source = RTS_STATIC_DEVICE && net = 91.142.72.0/22 ) then { bgp_community = add(bgp_community,(8905,1050)); #backup community bgp_origin = 0; bgp_path.prepend(48720); bgp_path.prepend(48720); bgp_path.prepend(48720); bgp_path.prepend(48720); accept; } if ( source = RTS_STATIC_DEVICE && net = 91.142.76.0/22 ) then { bgp_community = add(bgp_community,(8905,1050)); #backup community bgp_origin = 0; bgp_path.prepend(48720); bgp_path.prepend(48720); bgp_path.prepend(48720); bgp_path.prepend(48720); accept; } reject; }; output for ver 1.6.4 bird> show route export bgpcifra bird> show route preexport bgpcifra 184.0.184.0/21 via 91.211.219.10 on eth3.500 [bgpborder2 2018-07-18 11:55:54] * (100/0) [AS209?] 208.0.208.0/22 via 91.211.219.10 on eth3.500 [bgpborder2 2018-07-18 11:55:54] * (100/0) [AS26759i] 208.0.208.0/24 via 91.211.219.10 on eth3.500 [bgpborder2 2018-07-18 11:55:54] * (100/0) [AS26759i] 168.0.168.0/22 via 91.211.219.10 on eth3.500 [bgpborder2 2018-07-18 11:55:54] * (100/0) [AS265257i] 210.0.210.0/23 via 91.211.219.10 on eth3.500 [bgpborder2 2018-07-18 11:55:54] * (100/0) [AS9304i] 154.0.154.0/23 via 91.211.219.10 on eth3.500 [bgpborder2 2018-07-18 11:55:54] * (100/0) [AS36909i] 188.0.188.0/24 via 91.211.219.10 on eth3.500 [bgpborder2 2018-07-18 11:55:54] * (100/0) [AS49724i] 131.0.131.0/24 via 91.211.219.10 on eth3.500 [bgpborder2 2018-07-18 11:55:54] * (100/0) [AS52232i] 169.0.169.0/24 via 91.211.219.10 on eth3.500 [bgpborder2 2018-07-18 11:55:54] * (100/0) [AS37611i] 138.0.138.0/23 via 91.211.219.10 on eth3.500 [bgpborder2 2018-07-18 11:55:54] * (100/0) [AS264550i] 194.0.194.0/24 via 91.211.219.10 on eth3.500 [bgpborder2 2018-07-18 11:55:54] * (100/0) [AS42315i] 161.0.161.0/24 via 91.211.219.10 on eth3.500 [bgpborder2 2018-07-18 11:55:54] * (100/0) [AS262237i] 40.0.40.0/24 via 91.211.219.10 on eth3.500 [bgpborder2 2018-07-18 11:55:54] * (100/0) [AS4249i] 169.1.173.0/24 via 91.211.219.10 on eth3.500 [bgpborder2 2018-07-18 11:55:54] * (100/0) [AS37611i] 200.1.204.0/24 via 91.211.219.10 on eth3.500 [bgpborder2 2018-07-18 11:55:54] * (100/0) [AS27795i] 196.1.192.0/20 via 91.211.219.10 on eth3.500 [bgpborder2 2018-07-18 11:55:54] * (100/0) [AS15706?] ... bird> show protocols all bgpcifra name proto table state since info bgpcifra BGP master up 11:55:55 Established Description: CIFRA1 Router ID: 212.34.35.82 Preference: 100 Input filter: AS8905_in Output filter: AS8905_out Routes: 0 imported, 0 exported, 0 preferred Route change stats: received rejected filtered ignored accepted Import updates: 1415686 0 1415686 0 0 Import withdraws: 102 0 --- 1415788 0 Export updates: 1415361 0 1415361 --- 0 Export withdraws: 84 --- --- --- 707172 BGP state: Established Neighbor address: 212.34.35.81 Neighbor AS: 8905 Neighbor ID: 10.0.4.10 Neighbor caps: refresh restart-aware AS4 Session: external AS4 Source address: 212.34.35.82 Hold timer: 81/90 Keepalive timer: 3/60 output for ver 1.6.3 # birdc BIRD 1.6.3 ready. bird> show route export bgpcifra 193.9.244.0/22 dev lo [static1 2018-07-18 12:03:25] * (254) 91.142.72.0/22 dev lo [static1 2018-07-18 12:03:25] * (254) 91.142.76.0/22 dev lo [static1 2018-07-18 12:03:25] * (254) 91.211.216.0/22 dev lo [static1 2018-07-18 12:03:25] * (254) bird> show route preexport bgpcifra count 707133 of 1411221 routes for 709431 networks bird> show route export bgpcifra count 4 of 1411220 routes for 709430 networks bird> show protocol all bgpcifra name proto table state since info bgpcifra BGP master up 12:03:29 Established Description: CIFRA1 Router ID: 212.34.35.82 Preference: 100 Input filter: AS8905_in Output filter: AS8905_out Routes: 704077 imported, 4 exported, 4599 preferred Route change stats: received rejected filtered ignored accepted Import updates: 729703 0 3254 0 726449 Import withdraws: 657 0 --- 3265 646 Export updates: 1187031 460231 726796 --- 4 Export withdraws: 589 --- --- --- 0 BGP state: Established Neighbor address: 212.34.35.81 Neighbor AS: 8905 Neighbor ID: 10.0.4.10 Neighbor caps: refresh restart-aware AS4 Session: external AS4 Source address: 212.34.35.82 Hold timer: 74/90 Keepalive timer: 10/60 bird> Vladislav Grishin