Issue TOC Print full article Print this page Download as PDF E-Mail this URL     In this article Beyond the Virtual Executive Summary RFI: Storage Virtualization Solutions Rejected

Storage virtualization hasn't taken off as expected. A lack of standards, vendor infighting, and the absence of a true market leader have prevented vendors from delivering as promised.

Storage-virtualization vendors have touted technology in three broad categories: in-band, out-of-band and host-based. These serve as an alternative to the traditional RAID solutions that have come closest to virtualizing storage. In-band virtualization, championed by DataCore Software Corp., FalconStor Software and StorageTek, requires an appliance between the application server and the SAN switch. It has the potential to create bottlenecks, and its scalability is unproven. The out-of-band approach, as used by Compaq Computer Corp. and StoreAge Networking Technologies, in which the virtualization engine sits outside the data path, doesn't suffer from choke points. But the proprietary nature of these solutions has prevented this approach from becoming the dominant technology. Host-based virtualization companies, led by Veritas Software, employ virtualization software on each server host, a costly, hassle-filled strategy.

To judge the storage virtualization technologies' readiness, we sent an RFI (Request for Information) on behalf of the fictional Engulf and Devour Corp., a financial services company with a history of purchasing other institutions. Although the responses we received from Compaq, DataCore, FalconStor, StoreAge and Veritas were informative and well-thought-out, each one had an Achilles' heel, from Compaq's total forklifting requirement to Veritas' apparent lack of fault tolerance (the proposal promises high availability only).