Lost 6TB worth of data tonight

My Drobo Gen2 decided to lose 6TB worth of data tonight.

it’s loaded w/ 4x3TB drives. Formatted as a single HFS+ Journaled 16TB volume on a Mac Mini running 10.9.5. For a while now I’ve needed to upgrade two of my 3TB drives to 4TB and get some extra space. I’ve had one red light for almost a year, but I haven’t added anything else to the drive, so it hasn’t been an issue. Tonight I was using the files, copying some things from the file system, and then I went back later and everything was missing. All told, 6TB worth of data is no longer showing up on the Drobo. After a bit of a panic attack and a reboot I go into Drobo Dashboard. The drobo takes a good 5 minutes to populate in dashboard. Under the Capacity pie chart, it shows all 7.78TB of data. However, my red light is gone, shows green across the board. But, if I go into the Volumes tab, it shows only 1.7TB used.

I’m currently running disk utility on the drobo and it is sitting on “Checking catalog file” and has been for about 40 minutes. We’ll see what it looks like in the morning, but anything else to check would be great. Thanks.

Disk Utility did not find any errors. Now my capacity pie chart is in agreement with the volume descriptor. 1.78TB. So, I think I’ve lost 6TB of unreplaceable data. Wonderful. I’m running data recovery software on the drobo currently, but not holding out much hope.

hi janderfu, do you have access to diskwarrior?
that may be able to help you and has helped several other users when something has gone wrong and using a mac, like not being able to see volumes, or mount them etc.

am not sure what data recovery process you are using though if any recovery options are present (in terms of restoring a file to a particular location, usually it is best to only restore whole files to a different device (for example on a single drive computer, if a file is deleted by mistake, and software can recover it, it is best to recover to a different drive, just to minimise overwriting some other files that have not been restored yet, otherwise it can be potentially destructive).

you might be out of support? (as the gen 2 is fairly old, but you might be able to raise a 1 time paid ticket for the support team if you wish)

it might also be worth trying to fully power down the computer and drobo for about 5minutes, and then powering them up again, to see if things improve, and if those do not work, you might be able to try putting your drobo into a readonly mode, for example as mentioned here as it might help to stabalise and allow access to existing data:

3TB hard disks from all major brands have been extremely problematic in the past. I (and many others) wouldn’t recommend the use of them. In fact, there are a few class action lawsuits regarding them, just do a Google search with the keywords “3 TB hard disk class action suit”.

That being given in your situation you will probably want to do the following:

  1. Get a separate external hard disks withf at least a combination of 8 TB (2 x 4TB) of storage.
  2. Get one of those USB3 toaster type dual hard disk docking enclosures to hold the disks and connect it to your Mac.
  3. Download a trial of Prosoft Engineering’s Data Rescue 4 for Mac.
  4. Put your Drobo into read only mode.
  5. install your 4TB HD’s into the toaster.
  6. Format the 2 4TB HD’s in Disk Utility as 2 HFS+ disks.
  7. Launch Data Rescue 4, point it at the Drobo for the data rescue.
  8. Let it do its search and retrieval (it will take awhile).
  9. If it finds your missing 6TB, buy the product and then register it and rescue your 6TB of data to the 2 4TB hard disks.