RE: Root Guard

Thanks Bob!

Its clear now!

Regards,

--- On Fri, 6/4/10, Bob Sinclair <bob_at_bobsinclair.net> wrote:

From: Bob Sinclair <bob_at_bobsinclair.net>
Subject: RE: Root Guard
To: "'Abiola Jewoola'" <biola_y2k_at_yahoo.com>
Cc: ccielab_at_groupstudy.com
Date: Friday, June 4, 2010, 8:17 AM

If the original root bridge is still a root bridge,
then root
guard has done its job. To do that it has isolated the second switch
from the
original network. you will see that devices connected to Switch 1 cannot
communicate with Switch 2 (assuming root guard has been configured
consistently).

I do not see how that would cause a loop, since they are
in
different broadcast domains.

The basic application of root guard
is in a data center
environment, where you want to make sure that a customer
switch does not become
the root for the provider network. To accomplish this,
the provider
switch isolates the offending customer switch from the switched
network.
If that customer switch becomes the root in its own, isolated
network,
then that is OK with the provider.

HTH,

Bob Sinclair
  

From: Abiola Jewoola
[mailto:biola_y2k_at_yahoo.com]

Sent: Friday, June 04, 2010 11:04 AM

To: bob_at_bobsinclair.net

Cc: ccielab_at_groupstudy.com

Subject: RE: Root Guard

 
  
  Sorry I dont fully understand your
explanation.

  yea the switches are now claiming to be the root for a particular vlan.

  But if the idea was to protect the real root bridge from loosing its
status.and if the root inconsistent state segments the switches and each of
them are claiming to be the root. wont that cause a loop?

  --- On Fri, 6/4/10, Bob Sinclair <bob_at_bobsinclair.net>
  wrote:

  From: Bob Sinclair <bob_at_bobsinclair.net>

  Subject: RE: Root Guard

  To: "'Abiola Jewoola'" <biola_y2k_at_yahoo.com>,
  ccielab_at_groupstudy.com

  Date: Friday, June 4, 2010, 7:20 AM
  
  Hello Abiola,

  This is the intended operation of the root guard feature. The root

  inconsistent state serves to segment the broadcast domain, isolating the

  switches from each other. You should see that both switches are now
root,

  each for its own broadcast domain.

  HTH,

  Bob Sinclair

> -----Original Message-----

> From: nobody_at_groupstudy.com
  [mailto:nobody_at_groupstudy.com]
  On Behalf
Of

> Abiola Jewoola

> Sent: Friday, June 04, 2010 10:00 AM

> To: ccielab_at_groupstudy.com

> Subject: Root Guard

>

> Hello GS

>

> I am trying to configure rootguard.

>

> Here is the scenario.

>

> I have have four switches and one of them is the root bridge because it

> has

> the lowest bridge ID. I want to configure root guard so that the root

> bridge

> does not loose its status even if there is a better priority from other

> switches in the domain.

>

> I applied the spanning-tree guard root command on the interface

> connecting to

> the other switches on the. As i changed the priority on one of the

> other

> switches it became the root bridge,

>

> The port which had the rootguard command went to inconsistent mode. But

> it did

> not stop the other switch from taking over as the root bridge.

>

> i need some explanation plssss

>

> Regards

>

>

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Received on Fri Jun 04 2010 - 08:27:13 ART