Building on the old SAN
The Wake Forest University Baptist Medical Center in North Carolina began building its storage area network (SAN) around two years ago, says Bob Massengill, manager of technical services at the medical center, which operates 20 subsidiary hospitals as well as 90 clinics around the region. "We had to prove the concept" of a SAN to its internal users, which had been used to direct-attached storage (DAS) from IBM Corp. Going with a SAN, and then with EMC Corp. as its primary storage vendor took some getting used to. The medical center made the switch mainly because IBM's snapshot software for the mainframe required a full-volume update each time, where EMC's didn't. The center currently uses an older Symmetrix model 8830, with around 22TB of usable storage, and a newer DMX 2000 with 8TB of usable storage.
SAN usage started slowly because the SAN was a new idea and people were accustomed to the DAS world. Over time, though, many of the people in the end-user groups who had been reluctant found out that the SAN was only a centralized storage area, which the end users can continue to manage as they see fit. "I allocate," Massengill says, "then they do what they want or need."
The center began with two 16-port Sphereon 3000 McData switches. But after a year, users began clamoring to get their data over to the SAN environment, and an upgrade was needed, he says. That's when the center ordered its two 64-port Intrepid 6000 Series director-class switches, the second of which just went online. (The two older switches will continue to be used for production purposes until all the servers are moved over to the director switches and, eventually, will be used for backup only.) Now the first SAN-based application--e-mail--has been joined by financial applications and radiology.
The two director-class switches are separate from each other, by design, for backup reasons, Massengill says. Each of the 35 servers is attached to both switches, so in case one switch goes down the servers can still see the storage. In addition to needing two ports for each server, the StorageTek tape silo eats up many ports as well, he says.
Still coming is a full disaster recovery application for all the center's 400 servers. "This gets back to the benefit of not losing those two 16-port switches," Massengill says.
The original SAN connected around 7TB of storage with around 10 servers going through the two McData 16-port switches. He expects that the second 64-port switch will be fully populated by next summer, and then he'll probably get another for additional servers coming online to the SAN. In the meantime, he can always purchase a four-port card to turn one port into four, for a "couple of hundred bucks." That's cheaper than having a fully loaded director-level switch sitting around waiting to be used, he says.
--By Johanna Ambrosio
