On Oct 13, 2011, at 9:09 PM, Lorenzo Colitti wrote: On Mon, Oct 10, 2011 at 14:16, Curtis Villamizar <[email protected]<mailto:[email protected]>> wrote: Random number selection for router-id and this sort of recovery would solve the zero config OSPF issue related to router-id selection.
Not yet solved in existing zospf draft (afaik) but solvable. zOSPF says what do do in the case of collisions if the router with duplicate ID is on the same link, but not if it is elsewhere. However, I think it can be made to work like this: 1. On startup, choose the router ID you had on last boot (if available) or a random number. 2. Start OSPF with this router ID. 3. If you see a hello packet from a neighbour with your own router ID, you have a collision on the local link. Change it and back off. 4. If you see a router LSA listing you as a neighbour, but the router ID that originated this LSA is not a neighbour of yours, you have a duplicate router ID. Change it and back off. Are there any cases this does not cover? As to what to do if there is a collision, I'm not sure. zOSPF says what you and your neighbours should do if the colliding router is on your link, but I don't know if that's enough if the colliding router is elsewhere. Any OSPF experts know the answer to this? A new OSPFv3 mechanism is required in support of this. Today, any LSA received with the OSPFv3 router's Router-ID is considered to be a stale self-originated LSA. Thanks, Acee _______________________________________________ homenet mailing list [email protected] https://www.ietf.org/mailman/listinfo/homenet
