cef/process switching problem

Tue Sep 9 16:10:42 UTC 2003

ACL's are done in the CEF path also as long as you
don't have the "log" keyword on it that causes a punt.

Check the 'sh int stat' from the ingress interfaces and
see which ones are showing inbound process hits.

Rodney

On Tue, Sep 09, 2003 at 10:33:54AM -0500, Austad, Jay wrote:
> 
> It's 12.2 code.  show ip int e0 shows that CEF is enabled on the interface.
> Supposedly 12.2's CEF also handles policy routing (which is not being used
> on this router).  
> 
> > -----Original Message-----
> > From: Jason Frisvold [mailto:friz at corp.ptd.net]
> > Sent: Tuesday, September 09, 2003 10:24 AM
> > To: Austad, Jay
> > Cc: nanog at merit.edu
> > Subject: Re: cef/process switching problem
> > 
> > 
> > Not sure on the MC3810 (never used one), but I know that many of the
> > other Cisco routers didn't do CEF on ethernet until later revisions of
> > code...  There are other factors that kick it out of CEF as well.. I
> > believe ACL's and Route Maps are 2 of them..
> > 
> > On Tue, 2003-09-09 at 11:07, Austad, Jay wrote:
> > > I've got a cisco MC3810 with a bunch of DSL customers on it.  CEF is
> > > enabled, but when I do a show int stat, I see that almost 
> > 100% of the
> > > outbound packets on the ethernet interface are process 
> > switched, and not
> > > being matched in the route cache.  The Input looks just 
> > fine, and the other
> > > interfaces are borderline (usually 50% hit rate on the 
> > cache or a little
> > > less).
> > > 
> > > CPU is sitting pretty high on this box during the day, and 
> > I have strong
> > > suspicions that this is why.  :)
> > > 
> > > I can't seem to find any info on why this would be 
> > happening or how to
> > > figure out what's going on.  Anyone have any suggestions?
> > > 
> > > -jay
> > -- 
> > ---------------------------
> > Jason H. Frisvold
> > Backbone Engineering Supervisor
> > Penteledata Engineering
> > friz at corp.ptd.net
> > RedHat Engineer - RHCE # 807302349405893
> > Cisco Certified - CCNA # CSCO10151622
> > MySQL Core Certified - ID# 205982910
> > ---------------------------
> > "Imagination is more important than knowledge.
> > Knowledge is limited. Imagination encircles
> > the world."
> >       -- Albert Einstein [1879-1955]
> > 