RE: RAID10 explanation and mirroring setup

"Carlson@WHSmith" wrote: >> >> I've been following the RAID discussions and I'm having a bit of 'DBA >> block' when it comes to understanding RAID10. RAID01 is pretty easy: >> stripe, then mirror. Somehow the 'mirror, then stripe' explanation >> seems a bit vague to me. Could someone point me in the right direction? [cutting] You can minimize the risk of this >by making sure no drive's mirror drive is the same manufacturing lot >as it is so that if there is a manufacturing defect affecting the lot >the mirror is safe. [cutting] It's not just defects, disks from the same batch seem to have the same life span. If you have one from a batch fail then, in my experience, others in the batch are on their last legs and it's time to order another load of disks Paul Watson # WFSoftware Ltd # All answers given Tel: +44 1436 674729 # are pure fantasy Fax: +44 1436 678693 # www.wfsoftware.com/informix #

Paul Watson wrote: > "Carlson@WHSmith" wrote: > >> > >> I've been following the RAID discussions and I'm having a bit of 'DBA > >> block' when it comes to understanding RAID10. RAID01 is pretty easy: > >> stripe, then mirror. Somehow the 'mirror, then stripe' explanation > >> seems a bit vague to me. Could someone point me in the right direction? > > [cutting] > You can minimize the risk of this > >by making sure no drive's mirror drive is the same manufacturing lot > >as it is so that if there is a manufacturing defect affecting the lot > >the mirror is safe. > [cutting] > > It's not just defects, disks from the same batch seem to have the same > life span. If you have one from a batch fail then, in my experience, others > in the batch are on their last legs and it's time to order another load of > disks TRUTH! This has been my experience as well. Folk seem to think that 500,000hrs MTBF means the damned things will run forever. Art S. Kagel