neighbor ospf bird crash after local configure

[Martin Kraus]

On Sun, Nov 01, 2009 at 02:50:32PM +0100, Ondrej Zajicek wrote:
> Hmm, interesting. Could you describe what change was done in config file, 
> what is a topology of an affected part of the network and which router
> IDs were used by which routers, especially which router uses router ID
> 212.71.177.41?

I had to create a diagram which is (hopefully) attached to this mail as an svg.
I don't think I could describe it clearly in plaintext. 

There are five routers with respective IDs written inside the boxes. 
All are in ospf area 0.0.0.0. 
There is rest of the network behind routers with IDs 212.71.177.44 and
212.71.152.222 which id didn't put into the diagram.
There are some additional complexities, such as a separate ospf instance from
routers with IDs 212.71.177.41 and 212.71.177.42 but that wasn't affected so I
didn't include that either.

ID: 212.71.177.41 is a primary router running bgp to the provider and
exporting default route as an E2 route with metric2 10000.
All ospf costs are set to 10 except for costs to router ID: 212.71.177.44,
which is 15.

ID: 212.71.177.42 is a backup router running bgp to the provider and exporting
default route as an E2 route with metric2 11000. 
All ospf interface costs are set to 30.

ID: 212.71.177.58 is connected to ID: 212.71.177.41 and ID: 212.71.177.42
All ospf costs are set to 10.

ID: 212.71.177.44 is connected to ID: 212.71.177.41 and ID: 212.71.177.42 on
one interface and ID: 212.71.152.222 on second interface. There are additional routers
connected to a third interface.
All ospf costs are set to 15.

ID: 212.71.152.222 is connected to ID: 212.71.177.41 and ID: 212.71.177.42 on
one interface and ID: 212.71.177.44 on a second interface. There are aditiona
routers on a third interface.
All ospf costs are set to 10 except for cost to router ID: 212.71.177.44 which
is 15.


There is an asymmetry in interface costs with anything connected to router 
ID: 212.71.177.42, because it has been often selected as a gateway between
those parts of the network that are separated by this router and the router 
ID: 212.71.177.41. I prefer using router ID: 212.71.177.41, and this solved my
problem by making paths through ID: 212.71.177.42 more expensive.


The problem occured while reconfiguring router ID: 212.71.177.41, where I set
interface cost to router ID: 212.71.177.44(and of course ID: 212.71.177.42) 
from 10 to 15.

After running configure on router ID: 212.71.177.41, bird daemons crashed on routers 

ID: 212.71.177.44
ID: 212.71.152.222
ID: 212.71.177.58

leaving all the exported routes in the kernel routing table.

The bird daemon on router ID: 212.71.177.42 didn't crash. 

After I've started bird again, everything went to normal.

mk