Now that both Microsoft and VMware have officially announced the new released of their virtualization products it’s possible make an homogenous comparison between Hyper-V 2012 R2 (the fourth generation of Hyper-V) and vSphere 5.5.

VMware vSphere 5.5 introduces several news and scalability improvements, on the other side Microsoft Hyper-V 2012 R2 consolidate its features and improve what was already existing in the 2012 version, with a limited (but significant) new features. For example now, finally, some VMware old date features are mainstream also in Hyper-V, like VM hot cloning, hot disk resize (in this case also with the possibility to reduce the size).

For other comparison see also:

• Hyper-V 2012 e vSphere 5.1 (most considerations are still valid)
• Hyper-V 2012 e vSphere 5.0
• Comparing WS2012 R2 Hyper-V and vSphere 5.1

As usual, first to all, you can start from understanding the different terms used in each product: Know vSpeak? Learn to be Bilingual. But terms are almost simple to understand and fit the right context.

Then you must found some homogenous aspects to make the comparison, at least at technical level (but as written, it’s not so much important now). For numbers could be really easy, but numbers are not enough: for example memory management it’s still really different (VMware implement different technologies, Hyper-V only Dynamic Memory, only on some OSes)… so it’s not the same what you can do with the same amount of memory.

Hardware requirements are becoming much similar, considering that now also VMware require hardware assisted technologies. Hypervisor space requirements are completely different (ESXi could be installed on a 1 GB USB or SD card!) and also minimum memory requirements are singly different.

Scaling

As written memory management it’s really different and is not so easy to be compared. Dynamic Memory it’s better or worse? For supported OS, in my opinion, it’s an interesting approach (and VMware could implement it, considering that they already have the RAM hot-add feature), but of course having memory it’s always a better option. Remember also that the VMware Transparent Page Sharing feature have some limit with new OS (and also that it’s working on a page hash, and not on a real page comparison).

There are more difference in the supported virtual hardware: VMware has CPU and memory hot-add (but only from the Standard edition) and also NIC and other device hot-add. Hyper-V finally supporto disk hot-resize (and hot-add in version 2012) as also SCSI bootable disk. But VMware still support serial and paralle ports, USB device virtualization and also PCI passthought!

And VMware support more OS (also more Microsoft OS compared to Hyper-V). Also VMware can virtualize other hypervisor, including Hyper-V that could be useful for testing and labs!

Storage

On storage side it’s really interesting the new VHDX format that permit huge virtual disk (that now can also be hosted on ReFS volumes) also also vSphere 5.5. Caching and storage acceleration are slightly different, but present in both products. NTFS deduplication is now supported on Hyper-V, but only for VDI enviroment.

Note that both support thin provisioning in production (Hyper-V called it Dynamic Disks), interesting that Hyper-V include (from the 2012 version) both TRIM and UNMAP feature. Hyper-V also have Differential disks (but not recomended in production).

Networking

Networking it’s becoming most similar and the integration of teaming feature in Windows Server 2012 it’s really useful to avoid complicated 3rd part tools. Note also that not all services required a teaming feature, like, for example, Fail-Over Cluster heartbeat (in Hyper-V) or VMware vMotion or Hyper-V Live Migration network (that can work with multiple networks).

But (a good) Hyper-V network desing remain a little more complicated compared to a VMware design, considering also that teaming policies could not be set (in Hyper-V) at Team Interface level.

For the Software Defined Network approach, Microsoft is working on SCVMM side, VMware is working on the vCloud Networking and Security side (the old vShield edge) and now also on the NSX side.

High Availability & Resource control & Resiliency

Capability	Microsoft Hyper-V 2012 R2	VMware vSphere 5.5
		Free Hypervisor	Essential Plus	Enterprise Plus
Nodes per Cluster	64	N/A	32	32
VMs per Cluster	8000	N/A	4000	4000
Virtual Machine Live Migration	Yes	No	Yes	Yes
Shared-Nothing Live Migration	Yes	No	Yes (only from Web Client)	Yes (only from Web Client)
CPU Compatibility for Live Migration	Per VM (only one baseline)	No	Cluster EVC (several baselines)	Cluster EVC (several baselines)
Guest Clustering with Live Migration Support	Yes	N/A	No	No
Automated Live Migration	Yes	N/A	N/A	Yes (DRS/DPM)
Simultaneous Live Migrations	Unlimited	N/A	4 (1GigE) or 8 (10GigE)	4 (1GigE) or 8 (10GigE)
Live Storage Migration	Yes	No	No	Yes
Simultaneous Live Storage Migrations	Unlimited	N/A	N/A	4
Hot and Incremental Backups	Yes	No (some 3rd part tools)	Yes	Yes
VM Replication	Yes	No	Yes	Yes
Integrated High Availability	Yes (Fail-Over Cluster)	No	Yes (VMware HA)	Yes (VMware HA)
VM Lockstep Protection	No (3rd part tools)	No	No	Yes (VMware FT)
Guest OS Application Monitoring	Yes	N/A	No	App HA
HA handle storage failure	Yes	N/A	No	No
Cluster-Aware Updating	Yes	N/A	Yes	Yes
Failover Prioritization	Yes	N/A	Yes	Yes
Resource Pool	Yes (host groups)	Yes	No	Yes (DRS is needed)
Affinity & Anti-Affinity Rules	Yes	N/A	N/A	Yes

Conclusioni

One controversial aspect is the one about the real cost of implementing Hyper-V or vSphere: you can use cost per application (or service) metric (like suggested by VMware) or cost per host (like suggested by Microsoft). But honestly the software and hardware costs are not only that you have to consider. Implement and maintain has also other costs and those depends by you knowledge: for people skilled on Microsoft technologies maybe Hyper-V could be simplest, for people skilled on VMware technologies of course vSphere will become more easier. Note also that cost that VMware has a mandatory subscription (at least for the first year), Microsoft leave the Software Assurance as on option (but considering the new product lifecycle it’s becoming more a requirement rather than an option).

Anyway it’s almost true that the free version of Hyper-V give the most features (note that System Center VMM it’s not mandatory to handle and manage an Hyper-V cluster) and also there are not specific API limit in the free version (for example backup product for Hyper-V works fine). On the other side VMware differentiate with several editions, each with a different set of functions and has also unlock the memory limit of the free edition. And you have to remember that Windows Server 2012 R2 remain a new product with new licenses (or the requirements of a SA), unless you want to use the Hyper-V Server 2012 R2.

In my opinion it remain a personal and subjective choice that could also change case by case. Seems more difficult have mixed and hybrid approach with both solutions in the same company (or at least in the same division), considering the manageability complexity.

There is also a really good site (but not yet updated with those version) to compare vSphere with Hyper-V with XenServer and RHEV is Virtualization Matrix.