Virtualizing storage-intensive servers without big performance losses requires a level of storage performance that SANs weren't able to achieve. The obvious choice for Purdue seemed to be 10 Gigabit iSCSI, but cost was a deterrent. Purdue ultimately went with LSI 6Gbps SAS switching technologies, which offered the benefits of a failover SAN and the performance of an end-to-end native SAS 6Gbps data path --and which the school could afford.
"Even if our SAN goes down, we have enough local storage where we could limp along in another mode. Restoring more quickly is more important than staying up," Ellow says.
How to deal: Before choosing any vendor, be sure you understand the management capabilities, Barnes says. Server and storage virtualization can be simple: "You don't have to be a rocket scientist or have a degree in SAN management to take care of these things," he says.
At the end of the day, Elam says the benefits of virtualization are worth the trouble of grappling with these five challenges. "The pros far outweigh the cons just in its complete ease of use, stability, high availability, being able to replicate and do maintenance during the day, move stuff around as you need to and take hardware offline," he says "There are lots of things you don't have to come in on a weekend to do anymore."