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Re: High Processor Rates on Routers.

  • From: Chris Roberts
  • Date: Wed Nov 06 10:56:59 2002

On Wed, Nov 06, 2002 at 08:21:39AM -0500, [email protected] wrote:
> 
> 
> Ladies & Gentleman.
> 
> 
> Was wondering if it is common for processor rates on higher end Crisco boxes to race from 1 or 2 % show on the 5 second processor rate interval, to anywhere from 70 to 90 %, instanteously, then drop back down to 1 or 2 % after 10 seconds.
> 
> 

Check out for down interfaces, Serial/POS on the router. I've seen this
cause these spikes (although not normal for 10 seconds, more normally
about a second or so) every 30 seconds and make sure they're shut down.

Also check out OSPF to see if there is an interface flapping somewhere
in your network with the undocumented command 'sh ip ospf stat', which
will tell you what OSPF is doing, and look for a correlation between
the delta times and your high CPU utilisation.

BGP can cause a lot of processor utilisation when updates are received,
although this is not normally at accurate 30 second intervals, so I
wouldn't suspect this particularly.

Cheers,
-- 
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|  Chris Roberts ([email protected])  |
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