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Re: Initial Route Server Stats for MAE-East
From: Tim Bass <bass () dune silkroad com>
Date: Sun, 22 Oct 1995 16:48:37 -0400 (EDT)

On Sat, 21 Oct 1995, Mike O'Dell wrote:

remember that using pings to sample connectivity to a very busy
cisco router is not a very reliable probe for several reasons.
Returning pings is a low-priority task in the first place, and
they are rate-limited, so if the processor is busy processing
lots of BGP updates and several folks are fribbling with it 
using ping or SNMP, it is less than clear what they will see.


 Michael A. Nasto quips:

OK!  Agreed.  So then, what would you use? 

Have you ever been in a classroom and had a student raise his hand,
answer every question, ask intelligent questions, etc. just to prove
to the class how smart he or she is.    This is the premise of
the 'Two Mike's Interchange' above.  One says, HEY!  I know ping packets
are a lower priority than everything else in a *CISCO* router 
LOOK AT ME (wave wave). Then another kid in the class quips...
if PING is not what you would use, give us a better utility.

In fact... EVERYONE ( okay 99.73 percent :-) uses PING.  After all 
router LOAD is router LOAD.... and if a few ICMP packets can't get 
back in a subjectly reasonable time.. then DUH.... "da network
is busy......"  BGP updates take bandwidth just like any other packet.

Of course the 0.27 percent, zen routing gods of the universe just
feel the load and the harmonic BGP update patterns and PING between
the BGP updates.... for a better answer.

Sorry, I could not resist.... and apologize for the satire.  PING!!


| Tim Bass                           | #include<campfire.h>                | 
| Principal Network Systems Engineer |       for(beer=100;beer>1;beer++){  |
| The Silk Road Group, Ltd.          |           take_one_down();          |
|                                    |           pass_it_around();         |
| http://www.silkroad.com/           |       }                             |
|                                    |  back_to_work(); /*never reached */ | 

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