I recently floated the idea of implementing a mix of virtualization products in your data center as a way to better customize your virtual environments. The query was part of a larger discussion I wanted to get going about how VMware will compete when Hyper-V is generally released. I threw out the notion that data center managers might use, for example, Hyper-V for end-user file servers; VMware ESX, for apps that require dynamic load balancing, sophisticated disaster recovery and migration; and Xen for commodity Linux boxes.
The idea behind that supposition was to match your enterprise investments to appropriate workloads because, let’s face it, running everything on ESX is going to be expensive compared to other options. Big deal if you don’t get ESX-level features because you may get enterprise level features on silver-medal products.
A Supposition? No - more like a reality. If you look around, there is already VMware pervasive in the market, Parallels Virtuoso staking a claim in the MSP/hosting market, Xen making inroads in the Linux market, and other folks like Virtual Iron, Oracle and others about to pounce. Add-in the fact that IBM, HP and Sun each have their flavors of containers/partitioning. Oh... and don't forget that sometime soon you'll see virtual appliances (like rPath) that have embedded VMs from various vendors. And then, of course, Hyper-V.
Inside of 12-18 months, it will be a fact that data centers will have multiple virtualization technologies.
Strategically, organizations will need to prepare themselves for this - rather than create "virtualization silos." As you would expect the Invisible Hand to act, there are already a number of vendors looking closely at this space -- multi-virtualization management. Cassatt clearly comes to mind - but there will be others.
The next data center management "high ground" will certainly be those platforms that can leverage/control the multiple VM technologies out there, and dynamically control workloads, failovers, scaling, security, etc., including managing those machines that are not appropriate to virtualize at all. And my prediction is that the incumbent management platforms (i.e. OpenView & Tivoli) will not be in a position to do so. Look to the agile startups for that.