This may sound like a dumb question but can I run 32bit and 64bit Windows VM's on the same cluster? I have never worked with 64bit before and our consultant is recommending 64bit on our new Active Directory environment (we will have 40k+ user ID's that grow each semester)
Our hardware is IBM 3850 Xeon 7020 processors.
You can run 32 and 64 bit Windows on the same host / cluster without any issues. If you haven't run any x64 VMs yet, it may be the case that Intel VT is not yet enabled. You can check by running the below command. Your output should be the same. If not, then you'll need to restart the host, go into the BIOS and enable the option (it'll be listed as Intel VT / Virtualization Technology / etc). After you save the setting, it's a good idea to do a cold restart on the host. After you've made that change, the command should then have the below output and you'll be ready to create x64 VMs. You won't have to make any other changes to ESX.
esxcfg-info | grep "VT"