Hi Folks,
I have just spent a couple of days resolving some problems at the remote DR data centre, sorting out the problems caused by the over zealous use of a Vacuum cleaner of all things.
We have a backup server a SUN V480R with a Storedge 3510 and expansion attached which suffered a significant unexplained failure, all tracked back to an ID selector being touched by the nozzle of said vacuum cleaner - it looks like things went as follows over a period of time.
When the array was installed the setup was disks 0-9 were setup as a 10way stripe with disks 10 and 11 as hot standby disks. Over a period of time, a disk in the expansion (disk 3) failed and the and the first available spare (disk 10) built from the surviving mirror.
At this point the situation that existed left us exposed in a way which wasn't really appreciated, in that the one of the arrays had both mirrors of one part of the stripe. That would be the part that had the exposed ID selector switch, the one that the Vacuum Cleaner nozzle could change causing the failure of one whole stripe and one slice of an other stripe. The result as you can imagine was somewhat unpredictable, which is exactly what the Sun manual for the array says.
To add insult to injury the contents of the 3510 array, was the Legato Networker Backup Catalogue from the 24 drive ATL - making the recovery somewhat awkward.
What's the point of the story - don't let some idiot into a data centre with a Vacuum Cleaner.
Regards
Gull04