April 1, 2010 – I’ve been tracking how users configure their storage in virtualized environments for several years, via end-user surveys, and have noticed that NAS is gaining in popularity vs. other alternatives such as Fibre Channel SANs, iSCSI SANs, and direct-attached storage (DAS).
For example, an IDC survey of 168 IT professionals conducted in the fourth quarter of last year asked users “Which of the following storage types are currently deployed with your company’s server virtualization?” The results:
FC SAN: 35%
iSCSI SAN: 29%
Virtual storage appliance: 20%
Internal DAS: 20%
External DAS: 14%
Granted, IDC only surveyed 168 companies, but that’s the first time that I’ve seen NAS top the list (although statistically it’s practically a dead heat between NAS, FC SANs and iSCSI SANs).
In comparison, a survey of infostor.com visitors, conducted a few months prior to the IDC survey, had the following results (note: The InfoStor survey asked users to choose their primary storage configuration, and did not allow multiple responses):
FC SAN: 53%
iSCSI SAN: 28%
It’s meaningless to compare the results of the two surveys, but it’s clear from the IDC survey that, rather than trying to standardize on a single architecture for their virtual server storage environments, end users are moving toward a mix of two or more architectures.
I suppose that NAS’ strong showing is attributable in part to the rapid growth of unstructured file data in virtualized environments, as well as improvements in the latest versions of NFS. And, of course, to its relatively low cost, which has given NAS a boost not only in virtual server environments but across the board during the financial downturn. Also, the increasing use of “hybrid” or “unified” storage systems (i.e., NAS + SAN) may also be jacking up the percentages for NAS.
For more on the expanding applications for NAS, see “Evolving use cases for file-based storage,”
by IDC analyst Noemi Greyzdorf.