[Xorp-hackers] Question on RIB

[Ben Greear]

Pavlin Radoslavov wrote:
> Ben Greear <greearb at candelatech.com> wrote:
> 
>> I have a scenario of 4 routers.  Starting config is:
>>
>> A <-> B
>> B <-> C
>> C <-> D
>>
>> Also:
>> B <-> D  (high cost link)
>>
>> OSPF chooses the B-C link instead of the high cost link, and all is well.
>>
>> Then, I disconnect (remove the interfaces & OSPF config for those interfaces
>> with xorpsh)
>>
>> B & C
>>
>> OSPF correctly starts using the high-cost link.
>>
>>
>> Then, I reconnect B & C with the low cost link.
>>
>> It seems OSPF is trying to do the right thing.  Routes are deleted from
>> the high-cost link, but they do not appear on the low cost link.  The
>> reason appears to be this error in RIB.  I tried doing a 'commit' after
>> adding the interface and before adding the config to OSPF, but that did
>> not help.
>>
>> Any idea how RIB learns about the directly connected interfaces?  Looks like
>> I need to somehow make it learn faster...
> 
> I presume you already double-checked that that 10.2.3.3 indeed is a
> router directly connected to one of the new added interfaces.

After some more thinking...you may have a point here.  There might
be a race in my setup logic...ie the interface isn't fully configured
(or perhaps the peer isn't fully configured) when I poke xorp.

I'm going to add some more debugging logic near where RIB is searching
for the Vif and see what I can see.

Thanks,
Ben