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New Member

Spanning tree Confusion

I have a 6509 with 2 supervisor blades (one standby for failure of the main card). Both have the "Session 15/16" router daughter card. I am moving that standby to a 6506 that we have that does not have the router card. On the supervisor blade I moved to the 6506, I issued the "clear spantree root" command to set it to default on that card so it will not think it is the root on the 6506 - the 6509 is the root. This command didn't remove all spanning tree statements from the configuration. The following were left: set spantree fwddelay 15 1005; set spantree maxage 20 1005; set spantree priority 8189 1005. I cant determine how to remove those commands from the card. The show spantree command shows that the "designated root" is NOT the 6509 but the 6506 when this card is installed, which I beleive is causing problems in the network because I can only see traffic on the same network now (anywhere on our network) - not accross different networks. The other switches I have show the 6509 as the designated root.

What do I need to do to make this card no longer think it needs to be the designated root? It is currently pulled off our system and is quite disruptive to put back in and configure. Would moving the daughter card (session 15 - router) from this blade to the blade that exists in the 6506 be a better option?

Am I off base thinking that spanning tree is the problem?

New Member

Re: Spanning tree Confusion

I take it your running Hybrid and not Native IOS? I would set the priority high to something like 49,000 and see if the value changes, or configure uplinkfast. You can always blow away the config and re-apply if you have a copy of it.