Missing data; disk not emulated, steps to recover?

[bilderberger]

I recently moved all my disks to a new motherboard & CPU, to try and improve power efficiency.

 

Unraid seems to have taken to the switch just working fine.

 

The array was comprised of 2x 16TB parity disks and 2x 16TB data disks. While doing the hardware upgrade, I decided to remove the 2nd parity disk and instead keep it as a standby - so I removed this from the array. On a subsequent reboot I noticed that the second data disk was flagged as "unmountable" and that some of the share folders in the array were missing.

 

I had thought that the missing disk contents would be emulated from parity in such a scenario but this does not seem to be the case presently.

 

I ran xfs_repair from the terminal which reported a missing magic superblock and couldnt find the second one. SMART checks on the problem disk all seem fine.

 

The second parity disk is untouched, but presumably since I have removed it from the array already, this doesn't help me, though the most recent parity check should still be valid. 

 

To be honest, this is the first major issue involving data redundancy I've encountered with Unraid and I'm not entirely clear what the next steps should be and whether the missing data is still recoverable. Any tips from this sage community would be greatly appreciated.

[itimpi]

If you ran the xfs_repair from the terminal there is a significant chance you did not get the device name quite right.   Do you know what you used?

 

it is always better if possible to run xfs_repair via the GUI as it will automatically use the correct device name removing this as a potential source of error.

[bilderberger]

thanks - this was very helpful - I ran 
 

xfs_repair /dev/sdd

which apparently wasnt the correct device name. I didnt know it was possible to run xfs_repair from the UI, but now I do  its currently running and has found data so hopefully I'm on the right path to recovery. I'll post back here with an outcome - thanks very much! 🙏