On 2014/01/06 12:57 AM, Roman Mamedov wrote:
Did you align your partitions to accommodate for the 4K sector of the EARS?
I had, yes. I had to do a lot of research to get the array working
"optimally". I didn't need to repartition the spare so this carried over
to its being used as an OS disk.
I actually lost the "Green" array twice - and learned some valuable lessons:
1. I had an 8-port SCSI card which was dropping the disks due to the
timeout issue mentioned by Chris. That caused the first array failure.
Technically all the data was on the disks - but temporarily
irrecoverable as disks were constantly being dropped. I made a mistake
during ddrescue which simultaneously destroyed two disks' data, meaning
that the recovery operation was finally for nought. The only consolation
was that I had very little data at the time and none of it was
irreplaceable.
2. After replacing the SCSI card with two 4-port SATA cards, a few
months later I still had a double-failure (the second failure being
during the RAID5 rebuild). This time it was only due to bad disks and a
lack of scrubbing/early warning - clearly my own fault.
Having learnt these lessons, I'm now a big fan of scrubbing and backups. ;)
I'm also pushing for RAID15 wherever data is mission-critical. I simply
don't "trust" the reliability of disks any more and I also better
understand how, by having more and/or larger disks in a RAID5/6 array,
the overall reliability of that array array plummets.
--
__________
Brendan Hide
http://swiftspirit.co.za/
http://www.webafrica.co.za/?AFF1E97
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