setup new port-channel that consists of new ports only, once that is online add existing ISL ports to this port-channel. Yes the old ISL ports will be disabled when you add them to the channel but port-channel is still online. Once you add them go ahead and "no shut" and you are in business.
Hello there,  I'm facing the following challenge: I have 2 Cisco MDS9222i switches connected over a single ISL and I need to expand the link to a two channel portchannel. If possible I'd like to do this non disruptively. I was thinking of doing it like this:  As far as I can remember creating a portchannel is disruptive, so going directly from a single ISL to a 2 channel portchannel seems not the way to do this. Any tips?
Need to create a dual channel portchannel from a single ISL, preferably non 
disruptive