Re: Root bridge

I thought we cant change the MAC address of switch, I also tried to find out
the command to change the MAC in 3550/3560 switches. can you please help me
out???

On Thu, Sep 23, 2010 at 11:18 AM, Adam Booth <adam.booth_at_gmail.com> wrote:

> Hi Masroor,
>
> Chris gave you two potential answers, why aren't they acceptable?
>
> Just to recap what they are
>
> 1) Changing the bridge id of the switch you want to be root to have the
> lowest MAC Address
> 2) Increasing the priority on the other switches from the default 32768 to
> a higher value, so the unchanged switch will become root due to having the
> lowest priority
>
> Cheers,
> Adam
>
>
> On Thu, Sep 23, 2010 at 4:10 PM, masroor ali <masror.ali_at_gmail.com> wrote:
>
>> see i have a question in a document asking to make a root bridge without
>> changing priority, there must be a solution of this question..
>>
>> On Thu, Sep 23, 2010 at 12:59 AM, Chris Grammer <cgrammer_at_essilorusa.com
>> >wrote:
>>
>> > Change the MAC to 0000.0000.0001 on the switch you want to be root?
>> > Change the switch priority on all the other switches to be higher than
>> the
>> > switch that you want to be root.
>> >
>> > The bridge with the lowest Bridge ID wins.
>> >
>> > *Select a root bridge.* The *root bridge* of the spanning tree is the
>> > bridge
>> > with the smallest (lowest) bridge ID. Each bridge has a unique
>> identifier
>> > (ID) and a configurable priority number; the bridge ID contains both
>> > numbers. To compare two bridge IDs, the priority is compared first. If
>> two
>> > bridges have equal priority, then the MAC addresses are compared. For
>> > example, if switches A (MAC=0200.0000.1111) and B (MAC=0200.0000.2222)
>> both
>> > have a priority of 10, then switch A will be selected as the root
>> bridge.
>> >
>> > http://en.wikipedia.org/wiki/Spanning_tree_protocol
>> >
>> >
>> > <http://en.wikipedia.org/wiki/Spanning_tree_protocol>Chris
>> >
>> >
>> > On Wed, Sep 22, 2010 at 11:45 AM, masroor ali <masror.ali_at_gmail.com>
>> > wrote:
>> >
>> > > hi,
>> > >
>> > > is their any way to make a root switch without changing switch
>> > priority???
>> > >
>> > > --
>> > > Regards,
>> > > Masroor Ali
>> > > P Please don't print this e-mail unless you really need to.
>> > >
>> > >
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>>
>>
>> --
>> Regards,
>> Masroor Ali
>> P Please don't print this e-mail unless you really need to.
>>
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>

-- 
Regards,
Masroor Ali
P Please don't print this e-mail unless you really need to.
Blogs and organic groups at http://www.ccie.net