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Cat 6500 spanning tree - change MAC address?

Is there a way to change the spanning tree MAC address on a Cat6500 (Sup720 IOS 12.2(blah)SXblah, if it makes any difference)? We've had to set the bridge priority of our core Cats to 0 [see note 1] but we're just wondering if there's more tuning we can do.

[1] Don't ask - we're still investigating but there seem to be $50 WAPs out there that run STP with priority 0 by default; and yes, we know about root guard and bpdu guard.

Sam Wilson Network Development Team, Infrastructure Services Division Computing Services, The University of Edinburgh Edinburgh, Scotland, UK

Reply to
Sam Wilson
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The BIA is not configurable on the CAT6500 or any of the other switching platforms. The only option you have is to set the root priority lower.

Reply to
Anthony

Thanks. Can I ask a followup question, namely is the spanning tree bridge ID taken solely from some particular BIA rather than from any of other other possible addresses; or to rephrase that, do any of the techniques mentioned in, say, have any effect on STP bridge IDs?

Thanks,

Sam Wilson Network Development Team, Infrastructure Services Division Computing Services, The University of Edinburgh Edinburgh, Scotland, UK

Reply to
Sam Wilson

The spanning-tree bridge id is based off the idprom in the catalyst chassis. What the document is referring to is the SVI mac. Typically all routed ports/SVIs share the same mac, the document above gives direction on how to make the macs on the SVI different. This will have no effect on the bridge id as those addresses are not used in the root selection.

Hope this answers your questions. Anthony

Reply to
Anthony

The spanning-tree bridge id is based off the idprom in the catalyst chassis. What the document is referring to is the SVI mac. Typically all routed ports/SVIs share the same mac, the document above gives direction on how to make the macs on the SVI different. This will have no effect on the bridge id as those addresses are not used in the root selection.

Hope this answers your questions. Anthony

Reply to
Anthony

Yep - thanks a lot.

Sam

Reply to
Sam Wilson

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