On Tue, Aug 28, 2012 at 03:08:00PM +0200, Tore Anderson wrote:
I've run across a rather weird behaviour in BIRD 1.3.8 regarding the interaction between address(es) on the loopback interface and the OSPFv3 protocol. It seems that if there's no link-local address on the interface, BIRD fails to run OSPF in stub mode on it: ...
Question: What does ?Ignored? imply here?
That it is loopback and should not be used for active ifaces. But stub ifaces should be OK.
Also, why did the ?Primary? address change as a result of fe80:: being added?
This is a bug in primary address selection.
In any case, this means that without a link-local address being manually added to the loopback interface, the primary address of the router won't be reachable from the rest of the network, in turn causing problems for monitoring and possibly other protocols like iBGP.
This must be a bug, right? Being able to import the loopback interface of a router as a stub network into the IGP is pretty fundamental functionality. Also, link-local addresses aren't typically seen on loopback interfaces, so expecting them to be there doesn't make much sense to me.
OSPFv3 requires link-local address on iface to work, so there is just a missing exception for stub ifaces. Also note that some people suggest to use dummy iface instead of loopback iface for that purpose. But i don't know any valid reason why. Perhaps just to workaround similar issues in other software. -- Elen sila lumenn' omentielvo Ondrej 'SanTiago' Zajicek (email: santiago@crfreenet.org) OpenPGP encrypted e-mails preferred (KeyID 0x11DEADC3, wwwkeys.pgp.net) "To err is human -- to blame it on a computer is even more so."