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Re: slowing down every 60 seconds due to BGP scaner
From: Chris Konger <ckonger () internap com>
Date: Fri, 14 Sep 2001 14:11:00 -0700


Jesper Skriver wrote:

ping's to the router will show this, and cannot be used for anything,
what about end to end traffic ?

"David McGaugh" <david_mcgaugh () eli net> writes:

We've brought this concern up to Cisco before and they assured us that
everything is performing normally. You will see this when performing
router to router pings as well however, we have been told that packet
forwarding does not suffer. ICMP replies from the router (not through
the router) are given a very low CPU priority.

"Robert E. Seastrom" wrote:

Seconded.  Ping response times or lack of ping response from routers
signifies *nothing*.  Ditto for traceroutes, &c.  Ping *through* the
router, not *to* the router.

I think we're all in agreement here. Here's what I said Tang after he 
said what his platform was. The original message didn't have that info, 
so I sent several possibilities - all off channel. Wasn't on nanog-post
at the time (which is why the larger group was not CC'd).

-------- Original Message --------
Subject: Re: slowing down every 60 seconds due to BGP scaner
Date: Fri, 14 Sep 2001 12:13:46 -0700
From: Chris Konger <ckonger () internap com>
To: tang bing <tang_bing () yahoo com>

tang bing wrote:

We will put more memory and enable CEF on the line cards 
to see if its better .

If the customer is doing the test from their *router*, the lags
are due to the pings being process-switched and thus impacted by
the correlated bgp-scanner.

The best test is to ping *through* the routers via other src/
dst boxen (some servers hanging off the routers). That way the
'pings from the routers always being process-switched' won't
be impacted. Alternatively, you can ping for a long long time
and the 60 second spikes will wash out in the average (but will
still show up in the max value).

Hope this helps!

CK

PNAP Network Engineer                     415-364-2105 direct
InterNAP Network Services                 415-296-8611 fax
555 Montgomery, Suite 816                 415-596-4891 cell
San Francisco CA 94111                    888-841-2810 pgr


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