From owner-freebsd-isp Wed Jul 23 08:03:20 1997 Return-Path: Received: (from root@localhost) by hub.freebsd.org (8.8.5/8.8.5) id IAA22551 for isp-outgoing; Wed, 23 Jul 1997 08:03:20 -0700 (PDT) Received: from nak.myhouse.com (nak.myhouse.com [209.70.45.162]) by hub.freebsd.org (8.8.5/8.8.5) with SMTP id IAA22535 for ; Wed, 23 Jul 1997 08:03:15 -0700 (PDT) Received: (qmail 11052 invoked by uid 1000); 23 Jul 1997 15:02:48 -0000 Date: Wed, 23 Jul 1997 11:02:48 -0400 (EDT) From: zoonie To: Gary Palmer cc: freebsd-isp@FreeBSD.ORG Subject: Re: Monitoring the IP usage of a single IP address on an ethernet In-Reply-To: <8428.869636326@orion.webspan.net> Message-ID: MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: owner-freebsd-isp@FreeBSD.ORG X-Loop: FreeBSD.org Precedence: bulk On Wed, 23 Jul 1997, Gary Palmer wrote: > Just a warning: Cisco's IOS does allow you to turn on IP accounting, > and it does generate useful information, however, it comes at a > price. By default, Ciscos do something called `fast switching' which > means that the packet is delivered to the queue for the destination > interface as part of servicing the interrupt. Withouth fast switching, > the packet is just put in an input queue and processed as and when the > router gets round to it (thats a gross oversimplification). If you are > running routing processes (e.g. OSPF, EIGRP, BGP) on that box too, it > can lead to degraded service. i don't think that's the case gary, if i do a "sh ip int" on my router to show all ip interfaces it says that fast switching is turned on and if i do a "sh ip cache" i can see what's in the fast switching cache. i know about the different switching methods that cisco uses but i'm not all that up on when it is working and when it isn't. but, according to my router it's turned on. on the other hand with some of the problems that i have seen with the 11.x code at work who knows what the router is really doing (to be fair to cisco, most of that is DLSW related). at least it gets stuff from our network to the rest of the world in a reasonable amount of time. somebody mentioned in a follow up message that 11.2 has a traffic shaping feature that allows you to control bandwidth usage (i don't remember the exact text), that sounds like a neat feature but i would be wary about deploying the later versions of IOS on my network. > If you have a smart hub or a switch with a SNMP agent, and you just > want basic bytes in/out, thats probably the best way to go. If you you're right, this is the best way of doing it.....