Hello, I am coming to you with a weird one. I have simple iBGP setup between two routers which are interconnect through VLAN on IPv4 (/30) PtP link. For now RTR1 has all of the BGP feeds. I wanted to pass it to RTR2. Config on RTR2 is pretty simple: filter bgp_in { preference = bgp_local_pref; accept; } filter bgp_out { if proto = "CORE" then accept; reject; } protocol bgp RTR1 { local xx.xx.xx.xx as PUBLICAS; neighbor xx.xx.xx.xx as PUBLICAS; ipv4 { table master4; next hop self; import filter bgp_in; export filter bgp_out; }; } As soon as session starts up it loads routes, then unloads them and resets bird process. And it happens again and again and again... Logs doesn't seem very helpful: Dec 18 12:36:14 RTR2 bird[2009]: Started Dec 18 12:37:20 RTR2 systemd-journald[474]: [🡕] Suppressed 110623 messages from dataplane-bird.service Dec 18 12:37:20 RTR2 bird[2009]: RTR1.ipv4: Export state changed from DOWN to FEEDING Dec 18 12:37:20 RTR2 bird[2009]: RTR1.ipv4: Export state changed from FEEDING to PARTIAL Dec 18 12:37:20 RTR2 bird[2009]: RTR1: State changed to up Dec 18 12:37:20 RTR2 bird[2009]: RTR1.ipv4: Export state changed from PARTIAL to READY Dec 18 12:37:20 RTR2 bird[2009]: RTR1.ipv4: Fed up Dec 18 12:37:23 RTR2 bird[2009]: Netlink: Network is unreachable Dec 18 12:37:23 RTR2 bird[2009]: Netlink: Network is unreachable Dec 18 12:37:23 RTR2 bird[2009]: Netlink: Network is unreachable Dec 18 12:37:23 RTR2 bird[2009]: Netlink: Network is unreachable Dec 18 12:37:23 RTR2 bird[2009]: Netlink: Network is unreachable Dec 18 12:37:23 RTR2 bird[2009]: ... Dec 18 12:37:23 RTR2 bird[2009]: Kernel dropped some netlink messages, will resync on next scan. Dec 18 12:37:23 RTR2 bird[2009]: Shutting down Dec 18 12:37:23 RTR2 systemd[1]: Stopping dataplane-bird.service - BIRD Internet Routing Daemon... Dec 18 12:37:23 RTR2 bird[2009]: RTR1: Shutting down Dec 18 12:37:23 RTR2 bird[2009]: RTR1.ipv4: Export state changed from READY to DOWN Dec 18 12:37:23 RTR2 bird[2009]: RTR1.ipv4: stop import: rr 2 set 0 valid 0 pruning 0 pruned 0 Dec 18 12:37:23 RTR2 bird[2009]: RTR1: State changed to stop Dec 18 12:37:23 RTR2 bird[2009]: RTR1: State changed to flush Dec 18 12:37:24 RTR2 bird[2009]: RTR1: State changed to down Dec 18 12:37:24 RTR2 bird[2009]: Shutdown completed I also tried running the same config, but by starting BIRD processes manually as a root in foreground. It was able to load the routes, but only if pointed ipv4 channel of bgp protocol to custom separate table. As soon as I passed it into my master4 table process crashed with segfault. Unfortunately without meaningful traceback. I don't know if is important, but I use VPP as my dataplane. Pozdrawiam, Łukasz Jarosz