Of course, using vMotion requires shared storage, and there we hit a snag. My first choice, EqualLogic arrays, are just too expensive for this environment. Even a low-end disk array like an HP MSA or Dell MD3200 would cost more than $10,000 with six 300-GByte SAS drives, and that’s for a single controller model. Going to a dual controller system, which of course the enterprise storage guy inside me says is required, would add another $3,500 or so.
But if I installed a VSA with synchronous mirroring, like HP’s P4000 (Lefthand), StoreMagic, Falconstor NSS or Starwind HA, in each server, I could leverage the built-in RAID controllers, eliminate the storage controller as a single point of failure and theoretically improve reliability by storing two copies of all the data.
On the down side, I’ll give up some performance and host resources to the replication, but Dr. George’s I/O requirements are pretty light, and we have CPU to burn in the new config. Now I just have to choose a solution.