From: Chris (clarson52@comcast.net)
Date: Wed Sep 25 2002 - 23:03:21 GMT-3
What happens when the switch hosting the root guard command goes down, get's
turned off etc?
The ONLY way to ensure a switch or vlan will NEVER become root is to disable
spanning-tree on that switch or vlan, or turn off the switch.
ALL spanning-tree decision are based on the concept of a root. If you are
running spanning-tree there is a root somewhere. You cannot guaruntee that
any particular switch will never become root when this is the case. You have
to turn it off.
----- Original Message -----
From: "Voss, David" <dvoss@heidrick.com>
To: <ccielab@groupstudy.com>
Sent: Wednesday, September 25, 2002 9:03 PM
Subject: RE: Consensus
> So the consensus for the following (I'm adapting it a bit):
>
> Make sure that your switch "never" becomes root for vlan 20.
>
>
>
> root guard on the port hosting VLAN20 if you have 2 or more switches
sharing
> VLAN20
>
> and
>
> disable spanning tree for VLAN20 if you have 1 switch
>
>
>
>
>
> -----Original Message-----
> From: Balaji Siva [mailto:bsivasub@cisco.com]
> Sent: Wednesday, September 25, 2002 7:59 PM
> To: Nick Shah; Voss, David; ccielab@groupstudy.com
> Subject: RE: Consensus
>
>
> This makes more sense..though the config is actually made on the
> neighbouring switches !!!
>
> It is probably used on distribution/core to prevent small access switches
> from becoming root..
>
> B
>
>
>
>
>
> -----Original Message-----
> From: nobody@groupstudy.com [mailto:nobody@groupstudy.com]On Behalf Of
> Nick Shah
> Sent: Wednesday, September 25, 2002 8:42 PM
> To: Voss, David; ccielab@groupstudy.com
> Subject: Re: Consensus
>
>
> Set spantree guard is the ONLY sure shot way.
>
> I am willing to bet my $$$ on this one.
>
> To raise the odds on the bet :)
>
>
http://www.cisco.com/univercd/cc/td/doc/product/lan/cat5000/rel_6_1/config/s
> pantree.htm#xtocid2856623
>
> rgds
> Nick
> ----- Original Message -----
> From: "Voss, David" <dvoss@heidrick.com>
> To: <ccielab@groupstudy.com>
> Sent: Thursday, September 26, 2002 9:51 AM
> Subject: Consensus
>
>
> > I've been going through the threads on spanning tree and one thread that
> > never had a consensus was how to ensure a switch would "never" become
> root.
> > There is not a text I have found that addresses this. From what I can
> tell,
> > one option is to turn off spanning tree completely, the other to set
> > priority to 65535. Neither sounds appropriate to me.
This archive was generated by hypermail 2.1.4 : Mon Oct 07 2002 - 07:44:03 GMT-3