[c-nsp] IOS reliability

[Laurent Geyer]

On Wed, Jan 7, 2009 at 9:52 AM, Ross Vandegrift <ross at kallisti.us> wrote:

> On Wed, Jan 07, 2009 at 11:18:06AM +0000, A.L.M.Buxey at lboro.ac.uk wrote:
>
>  Most of the crashes have been related to SNMP.  For many MIBs, if you
> poll an object at the same time it is changed/removed, there's a race
> condition somewhere that kills IOS.  It's really horrible - we're just
> slowly whittling away at our SNMP view, losing management capabilites
> to keep the damn things from falling over.
>
> According to TAC, these crashes are rare and hard to trigger.  We've
> done it twice in a lab and four times in production.  On the upside,
> if you don't use SNMP, you're probably golden!


Interesting, haven't necessarily crashed a box with SNMP yet, but I've seen
the collection process triggering 100% CPU utilization following a link
state change.

CPU utilization normalized after disabling, or rather disallowing SNMP
access for a brief period.

- Laurent