[c-nsp] Ping priority on Cisco devices

[Ruben Alvarez]

Hi

I did figure it out today.  It was my fault there was a null route on that
router.  The Virtual interfaces for each DSL customer will create a /32
route on the router and most of the time OSPF had a route.  But
intermittently, those routes would drop and the ICMP would drop too.  I've
since removed the null route and it's rock solid.

Thanks.

-----Original Message-----
From: Ted Mittelstaedt [mailto:tedm at toybox.placo.com] 
Sent: Friday, April 10, 2009 10:07 AM
To: Ruben Alvarez
Cc: cisco-nsp at puck.nether.net
Subject: Re: [c-nsp] Ping priority on Cisco devices


Hi Ruben,

  If you running 12.3 or later IOS I'd suggest backreving to 12.2.  fast 
switching is
a problematical thing in the newer IOS on these older CPU cards.  I'd 
guess that
even if you have ip cef defined in your config, that cef isn't actually 
running.  what
does show ip cef, show cef day?

  IOS  12.1/12.2 is about the newest most people go on the NPE300

Ted

Ruben Alvarez wrote:
> Hi,
>
> Thanks for the reply.  It running at ~18% cpu and is a 7206vxr w/NPE300.
> This morning the loss cleared up.  I didn't collect enough data yesterday
to
> really get to the bottom of this, so I'll drop it as a Qwest megahost
issue.
>
> -----Original Message-----
> From: Ted Mittelstaedt [mailto:tedm at toybox.placo.com] 
> Sent: Wednesday, April 08, 2009 2:48 PM
> To: Ruben Alvarez
> Cc: cisco-nsp at puck.nether.net
> Subject: Re: [c-nsp] Ping priority on Cisco devices
>
> Ruben Alvarez wrote:
>   
>> 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?
>>
>> 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.
>>
>> Thanks.
>>
>>   
>>     
> What model is your router and can you post a config?
>
> What is CPU utilization on the router?  What is memory utilization on 
> the router?
>
> Ted
>
>