The move to virtualisation is all but inevitable, and there is very little question as to why. The benefits are incontrovertible, and the maturity of the virtualisation software available has moved virtualisation out of the realm of the test bed and into the realm of "have to have it.” It may be true that some companies are reluctant to switch over to a virtualised environment if they already have an existing system in place and substantial capital sunk into a data centre, it is much more likely that virtualisation will be strongly considered for any new installations.
With that in mind, one must consider the issue of virtualisation software. From early on, it was given that VMware would be the platform of choice, and it is not without reason. It is the most mature, has a stellar reputation and a superior feature set, and has had plenty of time to prove itself against more recent entries into the virtualisation market. For a CIO implementing virtualisation, it has to be said that you can’t get fired for buying VMware. But, until fairly recently, the decision was an easy one, and there was very little competition at hand. Such is no longer the case. A recent comparison in InfoWorld looked at VMware
, along with Citrix XenServer
, Microsoft Windows Server Hyper-V
, and Red Hat Enterprise Virtualisation
, and though VMware still garnered the high score, the comprehensive testing showed that all were up to the task.
In such a major project, the price tag is not the only consideration, but it is nonetheless a big one. Red Hat Enterprise Virtualisation, as an open source
product, does offer an advantage in terms of flexibility and lower cost, and the most recent version certainly brings RHEV into the limelight. But, VMware is still the only solution available that can accommodate a live storage migration, or moving a running VM between hosts without having to reboot. RHEV has caught up with VMware in offering page sharing and memory compression, a feature still lacking in other competitors, but in a feature comparison, the checkmarks are quickly appearing across the board. VMware too, goes further than the rest in OS support, with direct support of Mac OS X Server, FreeBSD, NetWare, and Solaris, making it the only real choice for a multi-OS environment or any environment that ventures away from Linux or Windows.
Before implementing VMware however, the CIO may be cautioned to review the licensing structure carefully, as it can be very complex, with multiple levels available and priced per physical socket. From a pure price perspective, RHEV is the simplest, with a flat subscription price per physical socket.
To answer the question at hand as to whether VMware is hands-down the best choice, just a few years ago the question would have been yes, without a doubt. But maturity of other platforms, along with an increasingly comparable feature set, makes the choice today a little more difficult.