[nsp] High CPU utilization from traffic with no destination interface?

rpcbind at speakeasy.net rpcbind at speakeasy.net
Thu Jun 26 12:35:27 EDT 2003


Are you running CEF? If so, then there's an implicit adjaceny to the null 
interface, so it should be handled extremely inexpensively. What does a 'show 
ip int' of the ingress interface show -- any chance there's some features 
there that may have tickled things badly?


On Thu, 26 Jun 2003, Temkin, David wrote:

> Does anyone know the actual IOS architecture for handling packets that enter
> the router where the router doesn't have a route for them?
> 
> I had a situation where a large amount of traffic was directed at one of my
> routers that didn't have a route to the destination and the CPU was pegged
> at 99%...  When I added an ACL blocking traffic to the networks that I
> didn't have routes to, the utilization dropped dramatically.
> 
> Thanks,
> 
> -Dave
> 
> 
> David Temkin
> S-I-G
> 401 City Avenue
> Bala Cynwyd, PA 19004
> http://www.sig.com <http://www.sig.com> 
> 
> 
> 
> IMPORTANT:The information contained in this email and/or its attachments is
> confidential. If you are not the intended recipient, please notify the
> sender immediately by reply and immediately delete this message and all its
> attachments.  Any review, use, reproduction, disclosure or dissemination of
> this message or any attachment by an unintended recipient is strictly
> prohibited.  Neither this message nor any attachment is intended as or
> should be construed as an offer, solicitation or recommendation to buy or
> sell any security or other financial instrument.  Neither the sender, his or
> her employer nor any of their respective affiliates makes any warranties as
> to the completeness or accuracy of any of the information contained herein
> or that this message or any of its attachments is free of viruses.
> 
> 
> _______________________________________________
> cisco-nsp mailing list  cisco-nsp at puck.nether.net
> http://puck.nether.net/mailman/listinfo/cisco-nsp
> archive at http://puck.nether.net/pipermail/cisco-nsp/
> 



More information about the cisco-nsp mailing list