Dell pushes SAS to the mainstream
Who dares to use serial-attached SCSI ?
By Chris Mellor | Techworld | Published: 11:51, 19 May 2006
As well as moving to AMD chips Dell has added serial-attached SCSI (SAS) drives to its storage offering. It has announced direct-attach PowerVault MD1000 arrays, the first from a mainstream vendor to use 3.5 inch serial-attached SCSI (SAS) disk drives. Customers can achieve up to 400 percent more bandwidth with 3.5-inch SAS drives versus traditional SCSI drives.
The MD1000 has a 4.5TB capacity with the option to expand up to three shelves for a maximum of 13.5TB. It can use 36GB, 73GB and 146GB SAS drives operating at 15,000 RPM; and 73GB, 146GB and 300GB drives operating at 10,000 RPM
SAS technology is the future for SCSI where the scope for further advances in bandwidth is limited. Ultra 320 SCSI is probably the last generation of traditional SCSI. First-generation SAS is only a 300MB/s technology but, as it is a serial and point-to-point connection scheme each drive gets the full 300MB/s bandwidth rather than having to share an ULtra-320 SCSI cable bus with the other drives hooked up to it.
SAS cables can be combined to provide higher bandwidth still. Seagate and others have come out with 2.5 inch SAS drives but Dell reckons its 3.5 inch SAS drives have a 30 performance advantage over 2.5 inch units. SAS controllers also have SATA (serial ATA) support built in providing expansion possibilities for cheaper and higher capacity SATA drives.
Hugh Jenkins, Dell's UK enterprise marketing manager Enterprise Marketing Manager, said: “This announcement focuses on customers who need to improve server utilisation with direct-attached storage."
We can expect other server system vendors to follow in Dell's footsteps, notably IBM and HP. Also we should start seeing networked SAS drive arrays appear from suppliers such as Nexsan.
The MD1000 is priced from about £1,399 (excluding VAT & delivery).
