Re: Spanning Tree Priority

Thanks Joe,

I agree with you. Was just trying to understand should we do it in real
network, i know ccie teaches you to configure vlan priority to zero.

thanks

On 22 May 2010 17:10, Joe Astorino <joe_astorino_at_comcast.net> wrote:

> Well, first of all the rules say your spanning-tree bridge priority is
> going to have to be a number that is a multiple of 4096. Somehow, that
> includes 0...I have labbed this up and it works. Let me clarify. You have
> a 16-bit field called priority. The priority field is futher divided into
> two pieces -- you have 4 bits for the actual priority, and 12 bits for VLAN
> ID. The priority field + VLAN ID gives you the overall bridge priority.
> That 4-bit piece must be 0 or a multiple of 4096
>
> Secondly, to make sure your root stays intact, you should configure the STP
> Root Guard feature. You are correct in that the spanning-tree root primary
> command is a one time only deal...it will lower your priority but if
> something comes on line later that is lower you are out of luck. My
> recommendation would be set your root to 0 and enable root guard where
> needed.
>
> Regards,
> Joe Astorino, CCIE #24347
>
> "He not busy being born is busy dying" -- Dylan
>
>
> ----- Original Message -----
> From: "naman sharma" <naman.prep_at_gmail.com>
> To: "Cisco certification" <ccielab_at_groupstudy.com>
> Sent: Saturday, May 22, 2010 4:56:33 PM GMT -05:00 US/Canada Eastern
> Subject: Spanning Tree Priority
>
> Hi,
>
> Is it advisable to configure Spanning-tree vlan priority to zero in real
> world. Although it will add the Vlan Sys-id to the priority in PVST mode.
>
> What is the best practice as configuring spanning tree root primary will
> only make sure that the switch becomes the root at that instant but you are
> still prone to issues if some switches is added later on with a lower
> priority.
>
> Any suggestion ??
>
> thanks
>
>
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Received on Sun May 23 2010 - 10:12:15 ART