Seeing an error message with that information anywhere along the line would have been extremely helpful.

A number of other common functions still need work. For instance, if you rename a VM in the client, it renames the VM in the display, but it doesn't rename the folders and files related to the VM. Thus, you can't create a VM using the old name. Further, if you migrate the "renamed" VM to another datastore while it's powered off, some of the files get renamed to the new VM name, but some don't—notably snapshots. In this instance, you're left with a nonfunctional VM after the migration. This seemingly simple step can be highly frustrating, and there's really no excuse for it. Simply renaming a VM shouldn't cause so much trouble.

Networking is still more complex than it perhaps needs to be, with service consoles, VMkernel interfaces, multiple default routes, and so on. It would be nice to see a consolidation of sorts there, with clearer definitions of networking functions and certainly clearer interpretations of commonly used networking terms. Configuring EtherChannel NIC bonding requires navigating a labyrinth of dialog boxes that becomes tiresome very quickly, although the addition of CDP (Cisco Discovery Protocol) support in ESX 3.5 goes a long way toward untying some knots by making it far simpler to identify connected switchports on each ESX host, provided you're using CDP-compliant switches. In some instances, though, this new feature turned up blank even when connected to a Cisco 6509 with CDP enabled. Speaking of networking, one of the more welcome hardware support updates is for selected 10-gigabit cards from Neterion and NetXen.

There are more new features to be found in ESX 3.5, such as IPv6 support for VMs, increases to host logical CPU counts and RAM counts (32 CPUs and 256GB, respectively), and support for as much as 64GB of RAM per VM. VirtualCenter 2.5 is more scalable as well, able to manage as many as 200 ESX hosts and 2,000 VMs. Another welcome improvement to VirtualCenter: VM client tool installations can now be automated on both Linux and Windows, thank you.

Tangentially related to the VI3 upgrade is the rather confusingly named V3i embedded hypervisor. This is likely to be the future of VM hosts in the not-too-distant future. An embedded hypervisor will remove the need for hard drives and harden the overall architecture. V3i is first-generation code, and probably only worthy of testing for the moment but promises much in terms of the future of virtualization. For instance, we will probably start seeing diskless servers from major vendors pre-loaded with V3i on bootable internal flash drives. Removing hard drive support of any kind in these servers promises to shrink their overall footprint and reduce the size of power supplies and server power consumption. This eventuality is a ways away, obviously, but doesn't seem that far-fetched.