[c-nsp] Ping priority on Cisco devices

[Oliver Boehmer (oboehmer)]

Ruben Alvarez <> wrote on Wednesday, April 08, 2009 20:04:

> All,
> 
> I've heard that Cisco devices handle ICMP at a low priority.  I found
> one post describing it handled in process-switching and not
> fast-switching. Does anyone have an article that explains that
> process and is it configurable?

Pings *to* the router are processed in process switching (as all/most
other packets destined to the router itself). Pings *through* the router
are switched like all others.

> The reason I ask is I see about 4% packet loss when I ping devices in
> our broadband aggregation network.  From the CPE to the router there
> is none, from my workstation to the router there is none, but if I
> ping the whole path I get a fairly consistent 4% loss.  I can't find
> any congestion or errors.  Ping from my workstation to the CPE are a
> consistent 60ms, aside from the 4% loss.

don't know what could be causing this. I would try to troubleshoot in
which direction the packets are lost, and troubleshoot further.. but
sounds strange..

	oli