Any guidelines to think about when considering virtualizing an exchange server?

Solution 1:

We're running virtualized exchange 2007 right now, and we have a BES. Though we're not to that level of users. Though we're running on VMWare ESX, we haven't had a problem with Microsoft support policies, and have been able to get support when we need it. Works for us.

The biggest factors of any VM project are memory and (in my opinion) disk infrastructure. If these mailbox servers really are low utilization, then using disk-backed virtual disks should be just fine. If they do have some high utilization message-stores, those should probably go on NPIV enabled fibre channel and have those LUNs direct-presented to the VM. Our Exchange 2007 servers take a lot of RAM, which can make them a hard fit in a VM environment. In my opinion, if your RAM needs are close to or over 16GB, then physical hardware is a better fit.

Solution 2:

VMware has a great page of resources with white papers on virtualizing Exchange: www.vmware.com/solutions/business-critical-apps/exchange/resources.html

We also did a nice podcast with community members asking questions to the VMware experts on this. blogs.vmware.com/vmtn/2009/01/virtualizing-exchange-roundtable-podcast-32.html sysadmin1138 is right -- getting your storage right is critical.

Because you can scale out with more VMs instead of scaling up with one big machine, we've put 16,000 Exchange mailboxes on one server -- so you should still have a bit of headroom with 150!