[c-nsp] Subject: Re: protecting cisco switches

Kevin.X.White at corusgroup.com Kevin.X.White at corusgroup.com
Mon Oct 8 11:57:12 EDT 2007

I've had a 2950 access layer meltdown in the same way with a broadcast loop
caused by a blocking uplink port intermitantly (twice in 3 months second
time for long enough to identify) not receiving any data (inc BPDUs) even
though up and looking healthy so it needless to say thought there had been
a change and the root was not on that port so started to forward with
disasterous results i.e. broadcasts killed most of the servers!
A reboot strangely fixed the problem untill we changed the box in a maint.
window - on further problems 7mths later.

I will say in Ciscos defence that once we added Loopguard and UDLD
detection to our configs, we failed to simulate the fault!


>Message: 5
>Date: Sun, 7 Oct 2007 22:09:11 -0700
>From: Mark Messier <mark at messier.com>
>Subject: Re: [c-nsp] protecting cisco switches
>To: cisco-nsp at puck.nether.net
>Message-ID: <0AB1721D-0A87-4F2C-8807-BB8A6BB1B2B2 at messier.com>
>Content-Type: text/plain; charset=US-ASCII; delsp=yes; format=flowed

>Revisiting this Aug 31 topic...   my simple set-up just
>blew up again.  I've got this:

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