We are in the process of upgrading from QC 11.00 to ALM 11.52. A member of our Infrastructure team has asked the following regarding using virtual servers for the environments as opposed to physical servers. Any assistance is greatly appreciated.
"Mark, the one item I would like to see is how ALM can handle being virtualized and what the best practices are for that. We try to Virtualize as much as possible, not so much to avoid hardware since we design for performance, not density – rather to allow for quicker recovery through items like snapshots and the ability to move the VM to other hosts rapidly."
We have been running ALM/QC on virtualized Windows servers using VMware products for about 5 years now without any problems. As long as the VMs you create meet the requirements of ALM/QC, and you don't overload your VM hosts inappropriately, you should be fine.
I have not seen any problems running Quality Center/ALM on a virtual environment too. We have been doing it for the last three years.
Just a note: if you decide to rely on virtualization don't forget about backup strategy. Backup strategy is equally important for both: hardware and virtual setups.