SAN-based intelligence: the Holy Grail of storage management? - Storage Networking - storage area networks

Computer Technology Review, Dec, 2003 by Bill Terrell

Another example use of the NSS Platform is to bridge SAN islands, particularly those using different vendor fabric switches. Often, smaller SAN islands are built around applications like databases, e-mail, or file servers. This approach is simpler to design and administer and confines the business justification to the application being deployed. However, these islands may use different vendors' fabric switches and storage systems--making it difficult to bridge them for the benefits of consolidation. One benefit of broader consolidation might be to take advantage of a SAN-attached tape library for centralized backup. An NSS Platform can be added to bridge each of the SAN islands to the tape library SAN. However, since it is not a switch, the ports of the various servers and storage devices in each island don't actually see each other--meaning there is no complex zoning to manage. Instead, the bridging between the SAN islands occurs through virtual volumes. In the centralized backup case, snapshots are created by the NSS Platform for each volume in each island that needs backup. Those snapshot volumes can then be assigned to the backup server in the backup SAN. This approach is simpler than trying to conjoin heterogeneous (or even homogeneous) SAN fabrics, is non-disruptive to the applications running in each island, and is more secure since the NSS Platform acts like a storage firewall between SAN islands with only selected volumes exported between SANs.

Will storage management benefit from the "Holy Grail"--the elusive SAN-based intelligence being promised? SAN "intelligence" resides everywhere today, in hosts, in storage arrays, and soon in the network itself. Migrating storage services to the network should depend on getting a complete solution that is incremental, complimentary to existing host-based and array-based intelligence, and complementary to existing networks and preferably fabric-agnostic. If approached this way. SAN-based intelligence--using elements like NSS Platforms--will have a major and long-lived impact on improving storage management and costs.

Bill Terrell is CTO of Troika Networks (Westlake Village, CA)

www.troikanetworks.com