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New Member

Etherchannel and STP ?

Looking for a bit of tech advice..

Each of my floors connect back to the core via a single uplink (fiber). Floor switches are 3560's. Floors 5,6 and 7 and the most important b/c

of the call center / services we provide.

I would like to use redundant links for each of these floors back to the core using etherchannels on both sides of the trunk.

Etherchannel will be LACP - active active on both sides.

On the core side, I will spread the etherchannel (LACP) across line cards and on each 3560 there will be an EC between Gi0/49 and Gi 0/50.

I have tested this in the lab and it works fine..but

With STP turned on for the 3 vlans in the trunk, the re-converge time is to slow once one of the ports in the EC goes down and comes back up.

If I kill STP for the 3 vlans, then there is no relearn time when the physical port comes back up in the EC.

Given the fact that my EC config is correct, do I really need STP in this scenario ?

Advice would be appreciated.




Etherchannel and STP ?

Well I would always run spanning tree protocol, no matter what. It's just not a good idea to do otherwise. Even if you don't have any "physical loops" in your network, you should always run it.

You could always run L3

But if I remember correct, on an Etherchannel, spanning tree BPDUs will follow one port within an etherchannel, but I'm not 100% correct about how that part works.

New Member

Etherchannel and STP ?

I agree with John, you should always run spanning tree.

Are you running rapid pvst everywhere?