We have an MSA60 with 12x4TB non-HP issue Seagate Constellation ES.3 drives connected to a P812/FBWC, on which I created a RAID6 over all of those disks with hpacucli and started to copy data on them.
Also, I pulled one of the drives during the early part of the copying procedure and replaced it, just to see how badly a RAID6 rebuild would affect write (and later read) performance for our production scenario. (It wasn't too bad, and it would've taken ~5 days to rebuild). This drive was at 75% rebuild.
Now I rebooted the DL385G7 with Debian Squeeze on it, to which the P812 is attached, and on reboot, no more array on the P812. The internal P410i array was intact. Hpacucli does see the drives, but lists them as unassigned. I googled a bit, and got the suggestion that re-creating the array the same would bring it back. I did do that. vgscan did not find the LVM volume.
I rebooted and went into ORCA. ORCA says that there are no volumes and no drives.
Now I'm a bit taken aback - what could be the problem? ORCA doesn't see the drives but hpacucli does? Could this be the problem why the LD that I created with hpacucli and already used doesn't pop up?
I have a replacement minisas cable and a replacement MSA60 I can play around with. A replacement P812 will take a while.
How do I debug this? What chance do I have getting the data back without the use of an external forensics company?
edit: Ok, now hpacucli doesn't see the drives either anymore. I think I'll go with replacing the MSA60 enclosure first.
edit2: Ok, ignoring all the "you're only a professional if you have the money for HP-disk-tax" snobbery, the following has transpired:
I did not check for the MSA actually being there:
=> ctrl slot=1 enclosure all show Error: The specified device does not have any storage enclosures.
could've told me all I needed.
- After swapping the cable and the port on the P812, I swapped the MSA60 (cold) and lo and behold, there was my array.
- The previously rebuilding disk at 70-something% is now marked "OK", prompting me to run filesystem checks. I suspect that the controller will continue the rebuild after the initial rescan.
Please not that I did not pull a disk "just for fun". I pulled it to be able to judge if RAID6 was sufficient for our needs in production. Which I would encourage everybody to do for a new configuration - doesn't matter if in storage, a piece of software or network equipment.