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Unmountable BTRFS Pool on Unraid

I have been having issues with one of my BTRFS pools on Unraid, it keeps locking up and then becoming unmountable.

I think I may know the root cause, but not sure yet.

The last time that this happened I had to use --repair, but it doesn't quite work through the gui, so here are the steps that I take to fix it.

When you have to do a --repair there is a Y/N question that has to be answered, but there is no obvious way to do this in the GUI.

DON'T BLAME ME IF YOU DELETE EVERYTHING

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REALLY DON'T BLAME ME

My Steps

  1. Place Unraid into maintenance mode.
  2. Run a Filesystem check, --readonly to make sure there are actually errors.
  3. I run a --repair to make sure that I get the device location correct. In this case its /dev/sdp1.
  4. SSH to the server, of use the web terminal interface and run: btrfs check --repair /dev/XXXX. This is relatively high risk, make sure you have tried to recover it other ways first.

Since this was your last chance to recover the pool, type Y and have a drink while it tries to repair your cat pictures.