[188865] in North American Network Operators' Group
Re: ASR-9K CPU troubleshooting
daemon@ATHENA.MIT.EDU (Rukka Pal)
Wed Apr 20 09:02:05 2016
X-Original-To: nanog@nanog.org
In-Reply-To: <CADy9NBCFivGb4TyPQ_bkJGRRQqWwDiUNuiWhz48gJk3SxHvfZQ@mail.gmail.com>
Date: Wed, 20 Apr 2016 15:02:01 +0200
From: Rukka Pal <regezos@gmail.com>
To: Micah Croff <micahcroff@gmail.com>
Cc: NANOG <nanog@nanog.org>
Errors-To: nanog-bounces@nanog.org
This document (BRKARC-2017) turned out to be very useful to determine the
possible root-cause. The utilization of the spp and netio processes
increase if the router/line-card is software switching traffic, in our case
ICMP. We will test the policing feature and implement it.
On Wed, Apr 20, 2016 at 1:17 AM, Micah Croff <micahcroff@gmail.com> wrote:
> I've experienced similar behavior on other platforms as well. Sometimes
> the output of the box is not correct. We were able to prove this to the
> vendor by conducting experiments and graphing the CPU. One of the
> protocols they said "couldn't possibly be causing this" turned out to be
> the root of the problem.
>
> I live by one rule when troubleshooting:
> The box is a lie.
>
> Micah
>
>
> On Tue, Apr 19, 2016 at 4:06 PM, Laurent Dumont <admin@coldnorthadmin.com>
> wrote:
>
> > It coincides with nothing else? More traffic? CPU increasing at regular
> > intervals every day without any obvious reasons is probably something
> worth
> > looking into!
> >
> > On 4/18/2016 2:14 PM, Scott Weeks wrote:
> >
> >>
> >> --- regezos@gmail.com wrote:
> >> From: Rukka Pal <regezos@gmail.com>
> >>
> >> How do you guys troubleshoot high CPU utilization on the ASR-9K
> platform?
> >> Detailed guides are available for IOS platforms, but I can't seem to
> find
> >> anything useful for the ASR.
> >>
> >> The average line-card (0/0/CPU0: A9K-24x10GE-TR) CPU utilization of my
> >> routers is about 10%, however recently I have noticed that 3-5 times a
> day
> >> it increases to 40% and stays there for about an hour (20% spp + 10%
> netio
> >> + the rest).
> >>
> >> I know this is well withing the acceptable range, but I am the kind of
> >> person who likes to understand every change in his network and during
> the
> >> investigation I had to realize that I simply don't have the tools to
> >> troubleshoot the ASR CPU.
> >> -----------------------------------
> >>
> >>
> >> On cisco: sho proc cpu
> >>
> >> scott
> >>
> >
> >
>
