[c-nsp] OSPF processes

[Justin M. Streiner]

On Thu, 15 Feb 2007, Sergio D. wrote:

> I was wondering if its a possibility that we have too many ospf processes
> running. In this one we have about 10 vrfs, I know on one of those vrfs we
> have a large amount of LSAs. Is there a limit on the ospf process amount or
> size of the database on each process? any response will be helpful.

The trick is finding out whether some other type of instability is causing 
the OSPF instability and driving up your CPU usage, or if your CPU usage 
is already high enough to cause your router to miss OSPF hellos...

I don't think there is a specific limit to the number of OSPF processes or 
LSAs that each process' link-state database can hold, outside of any CPU 
and memory constraints you might have.  Also, what kind of NPE do you have 
in that 7200?  It's a 7200 VXR chassis, correct?

You can do a few things:
1. Check the logs for interesting messages that might point to the cause 
of the CPU utilization spike
2. Make sure CEF is enabled globally and per interface.  The default on 
many interfaces is to enable CEF, but it's worth checking anyway.
3. Look at your running processes to determine what might be consuming 
your CPU resources.
4. Turn on OSPF event debugging (debug ip ospf events), turn your logging 
level up to debugging (logging trap debugging) if it's not there already 
and see what shows up in the logs.  I would be cautions about doing this 
from the console if console logging is enabled, or from a vty if you're 
using "term mon", as the log noise can be tough to read and can make the 
high CPU problem worse.

jms