[c-nsp] Core to access links. Use single etherchannel?

[Pete Templin]

Grant Moerschel wrote:
> Greetings all. We have a 6509 core with dual trunked layer 2 access
> switches connected on gig ports. So we use spanning tree in case one of
> the core to access connections fails therefore one link is always
> blocking. I'd like to get some opinions about improving this.  Is it a
> viable and recommended option to instead portchannel those two gig ports
> on both sides to both double the bandwidth and eliminate spanning tree
> issues?  If so, on the core switch side should one gig link be on, for
> example, 4/1 and the other on 5/1 in case a 6509 module fails? Thanks

If I remember correctly, whenever an Etherchannel changes from two or 
more members to one member (or vice versa), an STP reconvergence is 
triggered.  Assuming that to be correct, you'll still have an STP blip 
during a link/card failure.  :(

pt