YaSo

Got it, thanks for the reply.

EDITED FOR CLEARER EXPLANATION My story: 2 weeks ago, my server had 2x 24tb parity drives, data drives were a 20tb, a 16tb, and a few 14tb drives. Then I had a power outage and server would not boot.("no OS found") I used an old backup from BEFORE I added the 2x 24tb parity drives and started the server. I didn't notice that the array started with the 2x 24tb parity drives unmounted, and it SET my 16tb and 20tb drive to parity, as they were a few months ago when I made my OS backup. Some data was overwritten to the 20tb. When I saw I was missing media, (seasons of a TV show, some recent movies) and tried to diagnose. I wasn't sure of position of the drives, set them backwards (parity 2, parity 1) then after troubleshooting, resetting the drive config to try to mount, then eventually doing a data recovery on the 20tb to recover 2tb of an85% filled data drive, I am now about to try to start the array to see what I ended up losing. TO DO -add a data drive that lost data that wouldn't mount, back into the array (I pulled some data off it, now it needs to be formatted xfs to match other drives in array) -set a parity drive, or drives, since they were at first unassigned, then I didn't know 1 & 2 order and started array with them backwards (2&1) and parity is not trusted. Checking steps: 1-Should I make a new config with the parity drives and the 'data drive to be cleared' unassigned? Consensus is that the parity data is hosed after trying to figure out what happened. What settings to use if I will be adding 'new' parity drives? 2-Then I should add the data drive without the parity drives, start the array and let it format it when prompted? (Unraid Docs- Arrays - Adding to an array without parity protection) 3-Then STOP the array, add one or two parity drives, and start the array and let it build parity? 4-How bad is it if I only add back in ONE of my two 24tb parity drives, for a max of 106tb of data? I am considering keeping one 24tb drive 'unassigned' in case another drive dies in the near future, then I have another drive ready to go. Thanks in advance (Added a screenshot of the layout of my drives, 20tb disk 7 needs to be cleared / formatted, and may only add one parity drive, other unassigned as a future replacement drive)

To close out this post, I ran UFS Explorer on the 20tb, and found about 2tb of random files (the drive was at around 80% full, so I lost about 14tb of random media) I copied the found files to a spare external drive, and am about start to get the server back up and running, clearing the 20tb for data, adding in the 16tb again with it's data, putting in the 2x 24tb drives as parity, and then try to see what media I am actually missing.

I stopped the xfs repair scan after running for 5 hours. Got some more help in Discord. Consensus is that I should not rely on the two 24tb parity drives to have data, I should use something like UFS Explorer to see if there is any data on the 16tb (which was able to go through xfs repair) and the 20tb (which is what I just stopped running xfs repair) Unless someone else has any other ideas, I ordered a new flash drive to install linux on and I'll try to run linux on a USB for the server to try XFS Explorer to see what if anything is recoverable from the drives. FWIW, I am adding a txt file with the output of the 16tb drive I just re-scanned. (the first time, the terminal process scrolled beyond the top of the window) Unraid-xfs repair disk 4 16tb 26'07-12.txt

Update, XFS repair is still running in terminal on disk 7, 2 hours later..., just scrolling ...............

Thanks for the help, I ran that command on disk 4 (16tb) late last night, drive was showing as auto, now shows as xfs This morning I am running it on drive 7 (20tb) and terminal is scrolling . periods for almost half an hour, pushed my commands off the top of the terminal screen. I got a screenshot of it starting, and will post diagnostics (made while it's still running) i7-77-diagnostics-20260712-1120.zip

If there is any other info I can provide, please let me know. Disk 4 (16tb) and 7 (20tb) are listed as unmountable, not sure what steps i can take now, aside from formatting disk 4 and 7 and trying to see if the two parity drives can rebuild those two disks. EDIT: I was getting some (much appreciated) help in Discord, but it seems my situation is worse than what help could be given at the time.

Update, I was able to get diagnostics from unbootable USB drive, (I made a copy of files, just looked through them after restoring from backup, didn't know to look for anything a few days ago when crash happened) I got the correct drive assignments from the crashed USB files, the diagnostics were made after I swapped drives around. (Wish I found it earlier.) Disk 4 (16tb) and disk 7 (20tb) are unmountable. (I guess because old backup I used started the array with those as parity instead of data?) I have the server restarted in maintenance mode after speaking to someone in Unraid Discord, but I had to run out for a bit, waiting for steps to take next.

i7-77-diagnostics-20260711-0924.zip Diagnostics: After rebuilding OS flash drive with old backup from before I added larger (24tb) parity drives and made old parity drives data drives, then had a crash... -Then I made a new config and assigned the 24tb drives in what I think is the proper order as they were a week ago, and assigned two (16tb & 20tb) data drives in what I think was the proper slot order, (these were parity drives when I made my OS backup a long time ago).. -Then I started the array with 'Maintenance mode' and 'parity valid' checked... -Then stopped the array, took out the 16 & 20tb data drives from the 'slots', restarted array without maintenance mode, saved diagnostics attached above. EDIT, not the 5x 14tb drives were not moved physically or in Unraid setup since before I made my old backup Thanks in advance for looking at this. EDIT EDIT, I STOPPED the array after getting diagnostics so that Plex / other dockers and apps wouldn't write anything new to the array.

When I restart again with the 16tb & 20tb data drives unassigned to get diagnostics, I should NOT check the box for "maintenance mode"? (thanks in advance) Edit: restarted array without those two data drives, in 'normal' mode, and posted the diagnostics below.

This is the layout I 'THINK" the system was before the crash. Screenshots are after the new config, with preserve data on all drives. I checked the boxes for "maintenance mode" and Parity is valid". So I should start and stop the array, then 'UNASSIGN" the two 'data' drives (16 & 20 that were wrongly put back as parity by the old backup OS) leaving the parity drives in place, then RESTART the array with those two drives out, and post diagnostics? (Sorry for delay in my posts)

ALSO, is there any way to add the two 24tb drives as parity, not knowing which was in slot 1 or 2, and start in safe mode to not screw stuff up, just to check if the order is correct?

Not sure, but here's a thought... I originally had 8 drives, (16+20tb parity drives, 5 good 14tb drives,and a dead 14tb drive) I added two new drives. two 24tbs. 1st 24tb was added in same case location as the dead 14tb drive (slot 4 in Unraid) and 2nd 24tb was added as an extra drive with new data and power cables. When I would have added the two 24tb drives as parity, would Unraid likely show the slot 4 drive as the first of the two available unassigned drives, and the new addition (9th) as the lower of the two options in the dropdown list when I was adding them? I can check drive serial number and go off of that

If I am right, between the 16tb, the 20tb, and the two newer 24tb drives, I could not have had anything but the two 24tb drives as parity, right? Largest size drives have to be parity, right?

Yes, but the 'old' Parity drives (from before the crash) were unassigned. The backup was from before I got the new, larger 24tb drives.