Cat 6500 spanning tree - change MAC address?

Discussion in 'Cisco' started by Sam Wilson, Nov 17, 2005.

  1. Sam Wilson

    Sam Wilson Guest

    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
     
    Sam Wilson, Nov 17, 2005
    #1
    1. Advertisements

  2. Sam Wilson

    Anthony Guest

    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.
     
    Anthony, Nov 18, 2005
    #2
    1. Advertisements

  3. Sam Wilson

    Sam Wilson Guest

    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,
    <http://www.cisco.com/en/US/products/hw/switches/ps700/products_tech_not
    e09186a00801c9b4e.shtml> 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
     
    Sam Wilson, Nov 18, 2005
    #3
  4. Sam Wilson

    Anthony Guest

    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
     
    Anthony, Nov 22, 2005
    #4
  5. Sam Wilson

    Anthony Guest

    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
     
    Anthony, Nov 22, 2005
    #5
  6. Sam Wilson

    Sam Wilson Guest

    Yep - thanks a lot.

    Sam
     
    Sam Wilson, Nov 22, 2005
    #6
    1. Advertisements

Ask a Question

Want to reply to this thread or ask your own question?

You'll need to choose a username for the site, which only take a couple of moments (here). After that, you can post your question and our members will help you out.