A project I’m working on for an approximately half-billion dollar company in the health care industry has forced me to revisit Hyper-V versus VMware after a long period of inattention on my part, and it has become apparent that Hyper-V has made significant progress as a viable platform for at least medium enterprises. My key takeaways include:

• Hyper-V has come a long way and is now a viable competitor in Microsoft environments up through mid-size enterprise as long as their DR/HA requirements are not too stringent and as long as they are willing to use Microsoft’s Systems Center, Server Management Suite and Performance Resource Optimization as well as other vendor specific pieces of software as part of their management environment.
• Hyper-V still has limitations in VM memory size, total physical system memory size and number of cores per VM compared to VMware, and VMware boasts more flexible memory management and I/O options, but these differences are less significant that they were two years ago.
• For large enterprises and for complete integrated management, particularly storage, HA, DR and automated workload migration, and for what appears to be close to 100% coverage of workload sizes, VMware is still king of the barnyard. VMware also boasts an incredibly rich partner ecosystem.
• For cloud, Microsoft has a plausible story but it is completely wrapped around Azure.
• While I have not had the time (or the inclination, if I was being totally honest) to develop a very granular comparison, VMware’s recent changes to its legacy licensing structure (and subsequent changes to the new pricing structure) does look like license cost remains an attraction for Microsoft Hyper-V, especially if the enterprise is using Windows Server Enterprise Edition. 

Overall, it is apparent that Hyper-V has made gains, and I expect that when we get around to publishing our 2011 hardware survey results, that we will see that Hyper-V has made incremental gains in market share. Will Hyper-V ever overtake VMware? Almost certainly not, but as I mentioned in a recent blog on SUSE, healthy competition is always better for both the industry and users than a de facto monopoly.

Let me know what you think about Hyper-V versus VMware -- experiences, plans and anything else you want to share.