On 9/28/06, Steve Parr <SParr@xxxxxxxx> wrote:
How much would people trust SATA drives for their production servers? I would tend to stick with SCSI if I had a choice but I have inherited a few servers running with SATA drives. Just wondering what people have experienced. I feel tho if you are going to spend some decent money on a server doesn't make sense to scrimp on the hard drives just to save a little $$.
I know my way round HP Proliant servers very well (I used to do server support for them in the Compaq days, and plenty of hands-on since), so I'll use HP example to illustrate, but you can apply this to Dell / IBM / Others as well.
SATA is a low cost technology. It is not suitable for heavy disk access or for performance critical applications.
SATA disks: http://h18004.www1.hp.com/products/servers/proliantstorage/serial/sata/index.html "Ideal for... Customers requiring the best price advantage for entry level servers and bulk storage deployments in non-mission critical, low workload environments." OK - So Cost, cost and cost again. Thats the ONLY reason for considering SATA.
Warrenty: ftp://ftp.compaq.com/pub/products/servers/warranty/392512_EMEA_GB.pdf HP SATA disks come with a 1 year warranty. Even if you install them in a server with a 3 year warranty, they retain their 1 year standard warranty. HP SCSI disks come with a 3 year warranty. You could jump to the conclusion that SATA disks are 3 times more likely to fail than SCSI disks. You may be right, but it would be innapropriate for me to comment on that.
Personal experience: HP + SCSI = SMART. The SMART Array technology (originally from Compaq) has been around for years. It is tried and tested and easily understood. And interchangeable - you can swap one model for another with no pain. And supported by HPs SmartStart tool. SCSI RAID hardly ever fails as the result of a disk failure.
HP + SATA = ???. The drivers and controllers seem to be from Adaptec. There's no consistency in the upgrade path if you need to go from one controller to another, or swap disks between different model servers. The methods for managing a SATA RAID are not well understood, and can vary from one model of a server to another. SATA RAID is not monitored by the HP agents like SCSI is, so you don't get pre-failure warnings on SATA disks. SmartStart does not recognise SATA disks. SATA RAID is less resiliant and more likely to fail completely when you loose a disk.
Note: SAS (Serial Attached SCSI) is a SCSI technology and should be considered as such. http://h18004.www1.hp.com/products/servers/proliantstorage/serial/sas/index.html "Serial Attached SCSI (SAS) is the logical evolution of SCSI, including its long-established software advantage and the Serial ATA (SATA) electrical and physical connection interface." So the good bits of SATA and the good bits of SCSI.
I hope you now have a better understanding of the technology and can make a better informed decision as to what to do with your new servers.