We have recently purchased two Cisco 3750's to connect a new office to multiple, separate networks. The setup:
3750(new office) -> 3750(server room) ->Generic switch 1, Generic switch 2, etc.(server room).
The existing networks need to remain separate - there are separate runs for each existing network in the new office. Each existing network switch will connect to the 3750 in the server room via CAT6 patch cables.
The existing network switches are generic - no programming that I know of. There is one existing network that is running a Cisco 3750 with spanning tree.
Suffice to say, I tried to install the new switches and successfully choked the existing networks into submission creating havoc. I'm looking for the right way to do this with little to no changes to the programming of the existing switches - all 3rd party equipment.