[c-nsp] ip rib update process hogging CPU on 12.4.7d

[Rodney Dunn]

12 routes shouldn't cause that.

12.4(7d) is fairly old. I don't recall any bugs off the top of
my head in that area but you could try a later one or
give some more information around:

sh ip ro summ
sh ip bgp summ
sh ip protocols

And then some information around routing design to see if
there is some type of recursion issue going on (ie: bgp routes
recursing on to themselves, etc..)


 On Tue, Jun 03, 2008 at 06:47:21AM +0200, Nic Tjirkalli wrote:
> howdy ho,
> 
> >Look at 'sh ip route | incl 00:00' and see how much route
> >churn you are seeing.
> there is a bit of churn - around 12 routes but this can be expected on a
> full BGP feed.
> 
> the issue we have encounted though, is that the 7500s running a 12.3 image
> do not really mind this route churn, but on the 12.4 boxes, this results
> in the IP RIB Update hogging CPU
> 
> thanx
> 
> >
> >And/or watch 'sh ip cef events new' a couple times.
> >
> >Rodney
> >
> >On Mon, Jun 02, 2008 at 09:27:03AM +0200, Nic Tjirkalli wrote:
> >>
> >>howdy ho,
> >>
> >>Over the last few days, we have noticed that the IP RIB Update is
> >>consuming a large amount of CPU cycles on 2 CISCO 7500 routers running
> >>12.4.7d.
> >>
> >>We have several other CISCO 7500 routers taht receieve the same amount of
> >>BGP updates as the 2 with issues, but these routers are runninga  variety
> >>of 12.3 images and appear to be happy - no CPU hog caused by IP RIB Update
> >>process. All the 7500s are receieving a full BGP table.
> >>
> >>CISCO bug tnavigator has no mention of an IP RIB Update bug in 12.4
> >>images.
> >>
> >>was wondering if anybody else had observed similar behaviour.
> >>
> >>thanx for your time and any feedback.
> >>
> >>
> >>
> >>---------------------------------------------------------------------
> >>Alas poor Tagline! I knew it well...
> >>
> >>Nic Tjirkalli
> >>Verizon Business South Africa
> >>Network Strategy Team
> >>
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> 
> 
> ---------------------------------------------------------------------
> Someday, we'll look back on this, laugh nervously and change the subject.
> 
> Nic Tjirkalli
> Verizon Business South Africa
> Network Strategy Team
> 
> Verizon Business is a brand of Verizon South Africa (Pty) Ltd. This e-mail
> is strictly confidential and intended only for use by the addressee unless
> otherwise indicated.
> 
> Company Information:http:// www.verizonbusiness.com/za/contact/legal/
> 
> This e-mail is strictly confidential and intended only for use by the
> addressee unless otherwise indicated.