[98083] in North American Network Operators' Group
RE: Problems getting Cisco router and Motorola Nextlevel system to work together
daemon@ATHENA.MIT.EDU (michael.dillon@bt.com)
Tue Jul 24 17:04:14 2007
Date: Tue, 24 Jul 2007 21:25:49 +0100
In-Reply-To: <200707241123.40809.braaen@zcorum.com>
From: <michael.dillon@bt.com>
To: <nanog@merit.edu>
Errors-To: owner-nanog@merit.edu
> The router is currently configured to use IRB which is a=20
> hybrid process. =20
> The problems is that the IRB process is overloaded and is=20
> dropping traffic faster than it can process it.=20
Which NPE is in this router?
Basically, the 7200 has underpowered CPUs and if you force it to process
switch, then it handles a LOT LESS packets per second than you might
think. I expect that your config is forcing process switching rather
than fast switching.
The only three solutions are
A) run less traffic through the 7200 so that process switching can cope
B) stop using the feature that forces process switching
C) replace the 7200 with a 7300 which will probably not have CPU issues.
However, not knowing the specifics of what IRB is doing, I would advise
you to test a replacement platform before committing to it.
Oh well, maybe 4 solutions. If you are using a weak NPE such as NPE-200
you may be able to get some joy by upgrading to a more powerful one. For
instance an NPE-400 should handle roughly twice the load of an NPE-200.
--Michael Dillon
