Hello. We have bird 1.4.5 on servers with CentOS 6.5. We use it for advertise loopback sub-interfaces by OSPF. All subifs with /32 mask. We use IPVS+keepalived to bring up and down loopback subifs. Ifconfig: # ifconfig eth0.79 Link encap:Ethernet HWaddr 00:50:56:BA:37:70 inet addr:10.1.79.2 Bcast:10.1.79.255 Mask:255.255.255.0 inet6 addr: fe80::250:56ff:feba:3770/64 Scope:Link UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1 RX packets:34948906 errors:0 dropped:0 overruns:0 frame:0 TX packets:34154161 errors:0 dropped:0 overruns:0 carrier:0 collisions:0 txqueuelen:1000 RX bytes:3954197378 (3.6 GiB) TX bytes:3820153316 (3.5 GiB) lo Link encap:Local Loopback inet addr:127.0.0.1 Mask:255.0.0.0 inet6 addr: ::1/128 Scope:Host UP LOOPBACK RUNNING MTU:65536 Metric:1 RX packets:19544 errors:0 dropped:0 overruns:0 frame:0 TX packets:19544 errors:0 dropped:0 overruns:0 carrier:0 collisions:0 txqueuelen:0 RX bytes:977404 (954.4 KiB) TX bytes:977404 (954.4 KiB) lo:34 Link encap:Local Loopback inet addr:10.9.200.100 Mask:255.255.255.255 UP LOOPBACK RUNNING MTU:65536 Metric:1 OSPF works on eth0.79 interface. Problem - when IPVS+keepalived brings up any loopback subif - Bird additionally accept same network but with /8 mask and advertise it to the network.
From Bird log: Jun 11 10:36:23 bird: net accepted:10.0.0.0/8 2015-06-11 10:36:22 <INFO> net accepted:10.9.200.100/32
So in network I see: 10.0.0.0/8, ubest/mbest: 1/0 *via 10.1.79.2, Vlan79, [110/10], 00:02:06, ospf-0, type-2 and 10.9.200.100/32, ubest/mbest: 1/0 *via 10.1.79.2, Vlan79, [110/10], 02:12:08, ospf-0, type-2 Filter for the Bird to advertise loopbacks: protocol direct { interface "lo*"; # Restrict network interfaces it works with } filter connected_OSPF { # redistribute connected if ( source = RTS_DEVICE ) then { print "net accepted:", net; ospf_metric2 = 10; accept; } } As workaround we configure another filter that accept only /32 nets: filter connected_OSPF # redistribute connected prefix set DEVICE_NETWORKS; { DEVICE_NETWORKS = [ 0.0.0.0/0{32,32} ]; if ( source = RTS_DEVICE && net ~ DEVICE_NETWORKS ) then { print "net accepted:", net; ospf_metric2 = 10; accept; } reject; } Is it expected behavior of Bird to advertise prefixes like this or I missed something? Alexey