Re: STP Root port Eligibility

From: Joe Astorino (joe_astorino@comcast.net)
Date: Thu Mar 26 2009 - 14:11:21 ART

I think I see what you are saying now Bryan -- Are you saying to put root guard on the port that should never become the root port? That way, when it hears BPDUs from the root switch, it will shut down the port? Definitely "outside the box" way of using root guard, but I guess that would work!

"He not busy being born is busy dying" -- Dylan

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----- Original Message -----
From: "Bryan Bartik" <bbartik@ipexpert.com>
To: "Divin Mathew John" <divinjohn@gmail.com>
Cc: "oluwaseyi ojo" <sameoj@gmail.com>, "ftt" <femi0802@googlemail.com>, ccielab@groupstudy.com
Sent: Thursday, March 26, 2009 1:00:14 PM GMT -05:00 US/Canada Eastern
Subject: Re: STP Root port Eligibility

The task says that the port should never be "root port"...A port becomes
root port when it hears superior BPDUs. How can you block these?

You are not preventing the downstream ports from using this switch as root.

On Thu, Mar 26, 2009 at 10:54 AM, Divin Mathew John <divinjohn@gmail.com>wrote:

> Root guard allows the device to participate in STP as long as the
> device does not try to become the root. If root guard blocks the port,
> subsequent recovery is automatic. Recovery occurs as soon as the
> offending device ceases to send superior BPDUs.
>
> http://www.cisco.com/en/US/tech/tk389/tk621/technologies_tech_note09186a00800ae96b.shtml#diff
>
> Exactly...normal STP will function but.! a New root cannot takeover
> sending BPDU's from that port.! thats all
> Thanking You
>
> Yours Sincerely
>
> Divin Mathew John
> divinjohn@gmail.com
> divin@dide3d.com
> +91 9945430983
> +91 9846697191
> +974 5008916
> PGP PUBLIC KEY BLOCK @ http://www.dide3d.com/divin_Public_PGP_key.txt
>
>
>
> On Thu, Mar 26, 2009 at 10:21 PM, Bryan Bartik <bbartik@ipexpert.com>
> wrote:
> > rt. Even with root guard enabled on one port, other ports can be root po
> 

-- 
Bryan Bartik 
CCIE #23707, CCNP 
Sr. Support Engineer - IPexpert, Inc. 
URL: http://www.IPexpert.com 

Blogs and organic groups at http://www.ccie.net

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