Just had an HP 2.5" SAS 10k drive fail on a RAID5 array after about 2.5 years. It made me wonder if this was a fluke or an indication that 2.5" drives are less reliable than 3.5" SAS drives.

I've had many 3.5" SAS drives running for many years without any issues (knock on wood).

I would think that smaller drives would generate less heat and therefore be more reliable, but couldn't find any evidence of this.

I realize all drives will eventually fail and that it's a crap shoot with any particular model, but was hoping someone could point out some related studies or comment on the SCSI drive sizes they've found to be most reliable in servers.

Thanks.