Adaptec slips SAS under the wire
Serial storage killers escape early
Storage Expo, London Adaptec's upcoming family of Serial Attached SCSI adapters is on show here, even though it doesn't formally launch until next week. Already on sale is the 48300, a basic eight-port card offering mirroring and striping (RAID 0/1) on a 64-bit 133MHz PCI interface. It has four 3Gbit/sec internal SAS ports and four external, and lists for around £250.
Filling out the range are the 4800SAS and 4805SAS, which are microprocessor-based RAID controllers with 128MB of RAM each. They provide the full set of RAID, including 5, 10 and 50, and more ports too - two internal four-way connectors and one external. The difference between them is that the 4800 is PCI-X and the 4805 is PCIe (PCI-Express). Both cards support Microsoft's VSS and DPM.
Given that serial storage was supposed to save us from parallel hell by using easier to route and airflow-friendly round cables instead of ribbons, it seems odd to find Adaptec's SAS adapters fitted with four-way connectors that use flat 'octopus' cables. These are still smaller than SCSI ribbons though, and simpler for connecting external disk enclosures, too.
According to an Adaptec staffer, SAS is backwards-compatible with SATA and the same RAID card can run both, so you could for example host four SATA drives on one connector for bulk storage and four SAS drives on the other for frontline data. He added that, unlike SATA, SAS supports port expanders too, so each port can support multiple drives.