Hewlett-Packard has announced that its HP StorageWorks Modular Smart Array 1500 is the first storage array to support...
either SCSI or Serial ATA disc enclosures behind a single controller shelf. It expects to offer both types behind the same controller shelf soon.
Hybrid or dual-mode disc arrays employ the same idea as hybrid cars, which can use either petrol or electric power depending upon road conditions.
The MSA1500cs can deal with up to eight attached Serial ATA (SATA) enclosures and provide up to 24Tbytes (using 96, 250Gbytes SATA disc drives) of raw capacity. If the business needs SCSI reliability then attach up to four SCSI enclosures for a raw capacity of 8Tbytes (using 56, 146Gbytes SCSI discs).
HP's modular storage idea lets you use the same controller for either SCSI or SATA drives or both.
SATA drives are lower cost than SCSI drives and are useful, HP reckons, for "minimum I/O workloads such as reference data, archival and disc-to-disc back up". The SCSI discs are useful for more demanding I/O workloads, which need greater reliability.
Recently, HP also made a Fibre Attached Technology Adapted (FATA) drives announcement. Its Enterprise Virtual Array (EVA) 5000 can have either Fibre Channel discs or FATA drives in the same enclosure.
It supports up to 35Tbytes capacity with any combination of high performance Fibre Channel and low-cost FATA drives using existing EVA enclosures.
One reason for dual purpose is investment protection, said the company. Customers get more use out of their controllers. At the enterprise level customers can save money by using cheaper FATA drives for less critical data.
Where other suppliers would need two separate arrays to provide either Fibre Channel or SATA-type drives then HP can do it with one array. Similarly with SCSI and SATA. Customers may also save on floor space, HP said.
Ideally customers should have storage management software that helps them move data automatically across storage tiers. HP has a set of information management lifecycle (ILM) offerings, both products and services. There is also an HP ILM partner programme to generate ILM software products for HP kit.
This neatly fits into HP's adaptive enterprise strategy with customers moving data as its value changes across a spectrum of storage tiers, from fast disc to archival media.
No other supplier, other than HP, yet offers FATA drives. But the mixing and matching of FC and ATA or SCSI and SATA drives is becoming common.
EMC's Clariion CX arrays can have both SATA and SCSI drives in the same enclosure. Its Clariion DL700 is an array positioned as a disc library replacement for a tape library, one to be used to back up faster Symmetrix arrays. We might envisage future products combining these various drive types and functions.
Hitachi Data Systems' modular Thunder 9500 V Series arrays can have both Fibre Channel and ATA drives, with the latter positioned for compliance, archiving and back up, for example, of HDS' enterprise lightning arrays.
IBM TotalStorage FAStT900 Storage Server can use either SATA or Fibre Channel drive enclosures. IBM said it will be possible to have both types of enclosure in one FASt900 in the future.
Chris Mellor writes for Techworld.com