Tuesday, 5 February 2013

Windows Server 2012 Hyper-V R3 versus VMware vSphere 5.1

Back in April 2010, I wrote a post entitled “Microsoft Hyper-V R2 – why use it over VMware?”
Nearly 3 years later, it’s time to take a look at Windows Server 2012 Hyper-V R3 versus VMware vSphere 5.1.

Hyper-V (R3 in Windows Server 2012) finally deserves to be taken seriously as a hypervisor!

One of my biggest problems with Hyper-V and Hyper-V R2 was that, to commit a snapshot you had to shut down the VM; that was a very major flaw.  The number of problems we saw where an admin would take a snapshot before doing say Windows Updates, then commit the snapshot – and see it disappear from the GUI – but be completely oblivious to the fact that the snapshot files were still there, with the end result of having multiple snapshots balloon to dangerously large sizes and in worse cases lead to serious file system corruptions that could only be recovered from restoring from backup.

Finally, in Hyper-V R3, you can commit snapshots without shutting down the VM. VMware ESX/ESXi had this ability since pretty much year dot!

So with my biggest concern about Hyper-V now out the way, yes, I can finally start to look at Hyper-V R3 as a serious hypervisor, but there’s some way for it to go yet before I’ll rate it alongside VMware ESXi:

1) Windows Server 2012 Hyper-V R3 is too fat! You need a minimum of 16GB to install it. vSphere ESXi will install on 1GB and can even be auto-deployed to run in memory, something that’s not a feature in Hyper-V R3.

2) Administration: vSphere is really very easy to administer, for example – to create and enable a HA cluster it’s just a few clicks of the mouse, whereas Windows Server 2012 Hyper-V R3 still requires the clunky process of setting up failover cluster manager, CSVs and so forth.

3) Windows Server 2012 is a multiple purpose server trying to be something for everyone – and indeed it is very good – with Hyper-V just one role amongst many. On the other hand; VMware ESXi is built from the ground up to purely serve one purpose – be a hypervisor – and at that it excels. Don’t mention Hyper-V standalone – alas, to get the best features of Hyper-V R3 still needs the Windows Server 2012 version with Hyper-V role enabled

One big upper hand Hyper-V R3 has over vSphere ESXi 5.1, is the ability to have VHDX sizes of up to 64TB. VMware ESXi 5.1 is still stuck on the maximum 2TB VMDK size, something VMware need to address soon.

Cost could be suggested as an upper hand for Windows Server 2012 Hyper-V. If your environment is largely Microsoft, then you’ll be buying the datacenter licenses anyway for the VMs to run on top of the hosts, so using Hyper-V as the hypervisor makes sense, but it’s not as cheap as might first appear; VMware vSphere is simpler to administer saving OPEX costs, VMware vSphere can also achieve higher VM densities reducing CAPEX on hardware and further reducing OPEX….

Summarising: Windows Server 2012 Hyper-V R3 is now a serious hypervisor and a great step up from Hyper-V R2.

Further Reading


  1. What a blog!! Excellent

    A million thanks & love


  2. what features are missing from the Standalone version of Hyper V Server 2012? Nothing was missing in the standalone version of Hyper V 2008R2