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A total of 32 drives were removed from x4 decommissioned HP DL380 G6 servers (eight per server).
The setup of the eight drives per host was into two RAID Groups: RAID 1 = SLOT 1, 2 = ESXi OS RAID 5 = SLOT 3, 4, 5, 6, 7, 8 = VMFS Vol (hosting virtual machines)

Unfortunately there is some data that was not backed up prior to the removal of the drives, and now they are all in a pile mixed up.

What is the best way to put these drive back into the hosts without damaging the RAID groups the disks belong to?

Is there a tool that can be used to ready the RAID membership identifier on each drive? Not sure if ACU supports this!

TIA Danny

Danny
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    Interesting problem. I don't think you have any good options, though. – ewwhite Jul 17 '15 at 17:36
  • Your only luck would have to an old inventory with drive SN & position. Monitoring software can usually have such information. I checked with one I use and I can see slot# with drive SN. – yagmoth555 Jul 17 '15 at 17:52
  • The RAID configuration is stored—somewhere and somehow—on the drives. If you knew where to look, you could find that information using raw disk access. The location and format of this information depends on the RAID controller. Something you could do: make a raw backup of one of the disks, pop it in the system, and boot to the RAID controller to read the configuration from the disk. If you can do this with one disk, then you can do this with each disk individually to get the raid groups, or, if you're really lucky, even get the serial numbers of the disks in the configuration. – austinian Jul 17 '15 at 19:14

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Probably the safest thing to do would be to send them all to a company like Kroll OnTrack. They understand the on-disk format of HP's RAID. Since all of the drives are operational, this probably wouldn't be too expensive but you'll have to talk to the right rep to get them to understand what you want: identify and group, but do not recover.

If you have access to a DAS shelf like an MSA 2000, you could load all of the drives in and let the controller auto-detect the existing RAID configuration of the drives. You would need multiple shelves all connected to a single controller to get this to work easily, although you could probably do it with a single shelf and a bit of musical hard drives.

longneck
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The controller will erase the disks if you do this the wrong way...

Since HP Smart Array controllers store the array metadata on the actual drives, you can often move or relocate HP disk sets. However, there's some tolerance for drive displacement (slot reordering, etc).

So if the drives are moved together, the RAID is usaully intact. If you start doing that with multiple arrays with on-disk data... yeah. Not pretty.

An example from this weekend, trying to build a test environment from retired disks:

enter image description here

ewwhite
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  • I don't have the hardware available to test my method describe in my comment above, that of putting ONLY ONE disk in the system to see what configuration it belongs to. Does that seem like a safe way to identify the drives? I was assuming slot reordering was tolerated, there. – austinian Jul 17 '15 at 22:22
  • @ ewwhite, I was planing to spend some time today and install 16 of the total 32 disks into an old ML 5G that has 16 drive slots to try and ID the drive membership. Though I fear it's likely to be as per your comment "If you start doing that with multiple arrays with on-disk data... yeah. Not pretty." Still hoping there's a way to read the ARRAY membership ID (or similar) from the disks... – Danny Jul 22 '15 at 09:48
  • Just a thought. In your screen shot above, did the controller have prior arrays configured? I seem to recall that HP RAID CNTRLs store the Array metadata info on both the disk members and the controller itself. If I were to delete any config on the controller, then put multiple arrays with on-disk data into it, would I stand a chance of 'not' wiping them! – Danny Jul 22 '15 at 10:27
  • @Danny Array configuration is stored on the disks, not the controller. – ewwhite Jul 22 '15 at 11:36
  • Anyone else have any ideas or suggestions of utilities for identifying Array/Raid group membership stored on disks? – Danny Jul 23 '15 at 11:29
  • No. This is a mess. You won't be able to reassemble the RAID without the right disks. – ewwhite Jul 23 '15 at 11:30