[c-nsp] remove spanning-tree without being service effecting

James Urwiller jurwiller at americanbb.com
Thu Aug 2 17:39:32 EDT 2012

I have been having an issue with my few brocade devices in the ring not
blocking BPDU's properly towards my customers so when they hook a switch
up that has spanning-tree on by default, it causes a topology change.
Not cool!! :)  I have made Brocade aware of the issues, and they are
working on a firmware patch to fix the issue, but until then I want to
turn off all my spanning-tree so that I don't have random topology
changes occur.  Until I have verified that the Brocades block BPDU's
properly, I will have to manually shut down one of my links completing
the ring, and hope that if an actual equipment failure or fiber cut
happens that I can still get to that node to turn up the protection

Hopefully next year's budget will allow me to upgrade the appropriate
equipment so that I can use another ring protection mechanism such as
REP, ERP, or MRP.  This is just a stop gap until the brocades are fixed
or I can upgrade my core network.  With all the voice and video I have
running, spanning-tree wasn't really doing the trick for me anyway with
the long protection times.

I just wanted to know if there was an easy way to disable it across my
switch-to-switch links without causing any outages; from research, it
seems that bpdu-filter, and then portfast-trunk might do it with no hit
to the network.  I just wanted to see if that was truly the case.. I
have tried bpdu-guard with undesired results. 

I have no idea what to do if the broken link would come back up; but I
have to do something about customers equipment causing topology changes
all the time, and for now that seems like the best way; this firmware
bug in the fastIron code has really put me in a pickle!  

James Urwiller
Lead Internet Services Technician / Network Engineer
CCNA 11567125
American Broadband
402-426-6257 - Office
402-278-1875 - Cell
402-426-6273 - Fax
jurwiller at americanbb.com

-----Original Message-----
From: Andrew Miehs [mailto:andrew at 2sheds.de] 
Sent: Thursday, August 02, 2012 4:11 PM
To: James Urwiller
Cc: Pete Templin; cisco-nsp at puck.nether.net
Subject: Re: [c-nsp] remove spanning-tree without being service

Sent from a mobile device

On 03/08/2012, at 2:24, "James Urwiller" <jurwiller at americanbb.com>

> I got clarification on his suggestion, and I will proceed with that. I

> am aware of the risks, the question was how do I mitigate those
> your comment on leaving it alone doesn't help.  if you don't have 
> anything good to say; then don't.  Im sure the forum doesn't need your

> attitude, I know I don't.

Stupid question, why do you actually want to disable spanning tree?

How do you plan on setting up redundant links?

How will you connect remotely to a switch and enable it when one goes

What happens when the broken link comes up again suddenly?


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