[SOLVED] Got it running! I tested the theory that 'bad routes' were crashing ospf6d. The filter-list makes my ospf6d work! router ospf6 auto-cost reference-bandwidth 10000 area 0.0.0.0 filter-list prefix IN-OSPF6 in interface cxl1 area 0.0.0.0 interface cxl2 area 0.0.0.0 interface cxl3 area 0.0.0.0 ! ipv6 prefix-list IN-OSPF6 seq 3 permit 2607:f598::/32 le 64 ipv6 prefix-list IN-OSPF6 seq 99 deny ::/0 le 128 [BUG] I'm happy to turn on some debugging to show the routes crash ospf6d if anyone can tell me those commands. If I add a permit and force an session to restart, I can cause the running ospf6d to crash. repo: ipv6 prefix-list IN-OSPF6 seq 10 permit ::/0 le 128 router ospf6 no interface cxl3 area 0.0.0.0 interface cxl3 area 0.0.0.0 + Illegal instruction ospf6d Rudy