Can cross-stack Etherchannel cannot be implemented between Cat3750 and Cat2960?
I recently have Forwarding loops issue in my customer's network.
The setup is 3 Cat3750G-12S stack together using stackwise. they are connected to 6 Cat2960G-24TC-L via cross-stack etherchannel. And I do not know what happen, loops are being created. Can I confirm with you once again that this setup is wrong? If its wrong, what should the solution be to connect 6 Cat2960 to 3 Cat3750G stack switches?
Thanks a million in advance!!!
Yes, I have seen such issues and mostly it was due to physical loops. If
there is a server with dual NICs connected to two different switches, or if
there is a wireless client trying to associate with different AP's, we
witness such MAC flaps. In your case, I do not see any reason why a MAC be
flapping between PO4 and PO7 if the two switches are on different floors
unless there is some kind of physical loop created between these two floors.
Also, some of the error messages indicate issues between gi 1/0/5 and PO7
(but on a different vlan). So, yes, changing the ports to access mode could
help. But more than that, I would suggest you investigating the physical