Pointers please - OSPFv3 vs Cisco IOS XR

[Elmar K. Bins]

G'day all,

we were able to solve the problem today (thanks to my ingenious colleague).

In IOS XR, Cisco supports multiprotocol SNMPv3 and thus sets the bits correctly
for this. BIRD flukes on it. We got a lot of "I-bit mismatch(7)" messages.

Disabling rfc5838 support does the trick for us, since we're running ospf2 for
IPv4 and ospf3 for IPv6 (because...old IOS boxes in the mix in other places...)

    rfc5838 no;

My colleague supports the idea that this might be a bug in BIRD; if you need
debugging output to help, please ping me.

Yours,
    Elmar.


elmi at noir.de (Elmar K. Bins) wrote:

> > Do not see any issues on BIRD side. It seems to me that Cisco just resets
> > the exchange (by sending DBD flag I) when it should be done (or in Loading
> > state):
>
> I could not find any trace on the XR side, but I'll continue digging. I did
> actually expect it to be an MTU issue, but could find no proof of that. I
> also don't understand why OSPFv2 would work, but OSPFv3 would not.
>
> > I suppose that this exchage repeats indefinetly and 'show ospf neighbors'
> > on BIRD also shows the other side in ExStart/Exchange?
>
> Actually, the routers show as ExStart/DR and ExStart/BDR, which is also strange.