[j-nsp] OSPF next hop

[Wayne Tucker]

On Tue, Jul 24, 2012 at 12:36 PM, Aaron Dewell <aaron.dewell at gmail.com> wrote:
> Yes, Type Transit (2).  However, the Network LSA only includes 3 attached routers (should be 6 currently).  There are two Network LSAs in R7.  One has the interface IP of R1 (non-DR/BDR) with 3 attached routers (R1, R5, R6).  The other has the interface IP of R2 and shows 3 attached routers (R2, R7, and R8).  The interfaces on R3 and R4 are currently shut down.
>
> Further looking into it, there is disagreement all across this network about who is the DR and BDR.  Half the routers show one set, and half show the other.  I think that might produce some issues!

Wow, that is weird.  If L2 communication is good across the segment
then MTU or authentication mismatch would be my next guess.

It might be worth turning on OSPF tracing, if you haven't done so already:

set protocols ospf traceoptions file ospf-trace.log size 2m files 2
world-readable
set protocols ospf traceoptions flag error detail

There are other flags available, but I've found that "error detail"
almost always provides me the information I need.  At the same time,
it's pretty quiet under normal conditions (so I leave it enabled on
most of my OSPF routers).

:w