This week Dell began shipping the PowerVault MD1200 and MD1220, a pair of Serial Attached SCSI drive enclosures that support the 6Gb/s transfer rate released last summer, effectively doubling performance of the storage array. The company also unveiled a trio of PowerEdge RAID controllers to handle the increased speeds, which according to claims, boost I/Ops by about 35 percent and provide a level of fault tolerance through redundancy. The high-end PowerEdge RAID Controller (PERC) H800 supports up to RAID 60.
According to Gartner analyst Roger Cox, the news amounts to little more than keeping up with the Jones's. "It doesn't hurt Dell, because this is a US$1.2 billion a year marker and it's important for Dell to have these kinds of products. But I can't see where it gives them an competitive advantage," he said in a phone interview. "For example, Hewlett-Packard has the D2000 series, which has not been out long."
Physically, the D2600 is a close match with Dell's MD1200; both are 2U devices and both accept either 2.5- or 3.5-inch drives of various spindle speeds and types. Both can be linked with as many as seven additional enclosures for a maximum of 96 3.5-inch drives. HP's D2700 (2.5-inch only) maxes out at 100 2.5-inch drives, while Dell's MD1220 can accept as many as 192. Dell also supports solid state drives. Advantage Dell. For their RAID controllers, Dell licenses technology from LSI (as does IBM), while HP uses its own RAID stack, Cox said. He also said that Dell is competitive for these kinds of products, which are often referred to as JBODs, short for "just a bunch of disks." The MD1200 has a starting price of $5145, and the MD1220 (2.5-inch) starts at $5637. HP's web site shows the D2600 and the D2700 enclosures starting at $3399. The PERC H800 costs $649, about the same as a corresponding board from HP.
According to Howard Shoobe, Dell's senior manager of enterprise storage, the MD series helps to differentiate from the competition by offering a level of data security that other don't. "It enables a customer to take a PERC controller with two external SAS ports and connect to the same set of daisy chained JBODs to use all eight ports to increase performance," he said, adding that the configuration also provides a level of redundancy in case of accidental cable disconnect. Shoobe added that the card also can perform I/O load balancing across enclosures. "This is new functionality that's unique to Dell."
Cox is not so sure. To automate load balancing, there needs to be two host controllers in the server, he said. "And that would not be the usual case. But if you have them, you can balance I/O load between those RAID controllers," as a function of Windows Multipath I/O, not of the host adapter, he said. Dell's PowerVault MD1200 and MD1220 are available now, along with PERC H200 entry level and H700 and H800 premium RAID host adapters.
