thanks very much for the response ... very useful. I have one further question if i may ... i hope it makes sense ;-)
I currently have 6 Hosts in a cluster attached to dvswitch0 which is providing Management and vmotion portgroups. I have some new ESX Hosts that will be added to the cluster on a new dvswitch1. The vmotion network for the existing hosts is x.x.131.x, and a new vmotion network has been provisioned on x.x.144.x which is what the new ESX Hosts going into the cluster are currently configured for. The end result is to reconfigure the exisitng hosts in the cluster so that they are no longer on dvswitch0, but are on dvswitch1 which will be providing portgroups for management, ip storage, vm guest traffic etc etc. All Hosts in the cluster ultimately end up on dvswitch1
The proposed solution, to prevent vm downtime, is to create the new 144 vmotion portgroups on dvswitch0. Change the portgroup on the exisitng hosts dvswitch0 to the new 144 pg's and change the IP's for the vmotion portgroups from x.x.131.x to x.x.144.x. (this way the vmotion ip addresses for the current Host is on the same subnet as the new Hosts being added to the cluster)
Evacuate an exisitng Hosts vm's onto one of the new ESX Hosts added to the cluster, and then reconfigure the exisitng Host from dvswitch0 to dvswitch1. Repeat for the remaining 5 exisitng hosts in the cluster. Once all the Hosts are on dvswitch1, rebalance the vm's and remove dvswitch0
So my question ultimately is as follows ... if i have an esx host attached to dvswitch0 with vmotion pg's configured for x.x.144.x subnet, and another esx host on dvswitch1 with vmotion pg's configured for x.x.144.x subnet .... can i vmotion between the 2 Hosts ? or will the fact that the vmotion pg's are on 2 different dvswitches prevent this from happening in some way ? the vmotion portgroups btw will have the same names on both dvswitches, and there will be 6 of them to facilitate multi-nic vmotion
I hope thats clear ;-) any info would be much appreciated