February 7, 20233 yr Hello, My array had some file corruption due to a power loss during a large file transfer. I followed the below instructions from the UnRaid Wiki " The procedure If you are running a very old version of unRAID, such as v4.7 or older, skip down to the next section. Stop the array Unassign the old drive if still assigned (to unassign, set it to No Device) Power down [ Optional ] Pull the old drive (you may want to leave it installed for Preclearing or testing) Install the new drive Power on Assign the new drive in the slot of the old drive Go to the Main -> Array Operation section Put a check in the Yes, I'm sure checkbox (next to the information indicating the drive will be rebuilt), and click the Start button The rebuild will begin, with hefty disk activity on all drives, lots of writes on the new drive and lots of reads on all other drives All of the contents of the old drive will be copied onto the new drive, making it an exact replacement, except possibly with more capacity than the old drive." After the parity check completed I noticed that all my shares were empty and dockers lost data that was there before the rebuild. I am currently running another parity check. 52Mins in and it has not found any errors. Is the data lost? Thanks
February 7, 20233 yr Community Expert Not necessarily related, but probably not what you intend appdata shareUseCache="prefer" # Share exists on disk1, disk3, appcache, plexameta Your disks don't seem to have much data. Is that expected? 2 hours ago, Duckysownyou said: had some file corruption How did you take care of that? Rebuild will typically not fix corruption. Were any disks unmountable? Did you format anything?
February 7, 20233 yr Author 3 minutes ago, trurl said: Not necessarily related, but probably not what you intend appdata shareUseCache="prefer" # Share exists on disk1, disk3, appcache, plexameta Ahh, cant say that was intentional. thanks for pointing that out! 3 minutes ago, trurl said: Your disks don't seem to have much data. Is that expected? yes, I had maybe 600GB on the whole array. I hadn't started migrating from my old NAS yet. 3 minutes ago, trurl said: How did you take care of that? Rebuild will typically not fix corruption. Were any disks unmountable? Did you format anything? The disk was no longer mountable or readable. when I rebuilt it informed me that the drive would be erased
February 7, 20233 yr Community Expert 1 minute ago, Duckysownyou said: The disk was no longer mountable or readable. when I rebuilt it informed me that the drive would be erased No, it wouldn't have told you the drive would be erased if all you did was rebuild it. Which disk was it? Did you format the disk?
February 8, 20233 yr Community Expert Did you actually have a disabled disk? Or was the disk just unmountable? Rebuild typically won't fix unmountable. Looks like disks 2, 4, 5 might all be empty. Did you format them all?
February 8, 20233 yr Author my apologies I actually followed these instructions: Rebuilding a drive onto itself There can be cases where it is determined that the reason a disk was disabled is due to an external factor and the disk drive appears to be fine. In such a case you need to take a slightly modified process to cause Unraid to rebuild a 'disabled' drive back onto the same drive. Stop array Unassign disabled disk Start array so the missing disk is registered Important: If the drive to be rebuilt is a data drive then check that the emulated drive is showing the content you expect to be there as the rebuild process simply makes the physical drive match the emulated one. Is this is not the case then you may want to ask in forums for advice on the best way to proceed. Stop array Reassign disabled disk (optional) Tick the box to start in Maintenance mode. If you start the array in Maintenance mode you will need to press the Sync button to trigger the rebuild. The advantage of doing this in Maintenance mode is that nothing else can write to the array while the rebuild is running which maximises speed. The disadvantage is that you cannot use the array in the meantime and until you return to normal mode cannot see what the contents of the disk being rebuilt will look like. Click Start.to initiate the rebuild process.and the system will reconstruct the contents of the emulated disk, as far as I recall I did not select format. Its been a while so the details are a bit fuzzy.. (rebuilding the array took over a day) I just want to make sure parity is indeed working so I can minimize the chance of this happening again. and if it was my fault what I did so I dont do it again. appreciate the assistance. As I am fairly new to UnRaid.
February 8, 20233 yr Author 2 minutes ago, trurl said: Did you actually have a disabled disk? Or was the disk just unmountable? Rebuild typically won't fix unmountable. Looks like disks 2, 4, 5 might all be empty. Did you format them all? Yeah it was disabled. Disk 2,4,5 never really had anything on them
February 8, 20233 yr Community Expert Which disk did you rebuild? 1 minute ago, Duckysownyou said: Important: If the drive to be rebuilt is a data drive then check that the emulated drive is showing the content you expect to be there as the rebuild process simply makes the physical drive match the emulated one. Is this is not the case then you may want to ask in forums for advice on the best way to proceed. Did you check that the emulated drive had the expected contents?
February 8, 20233 yr Author 1 minute ago, trurl said: Which disk did you rebuild? Disk 1 - ST16000VE000-2L2103_ZL2E24CM - 16 TB (sdg) 1 minute ago, trurl said: Did you check that the emulated drive had the expected contents? Yeah, everything looked good on the emulated drive
February 8, 20233 yr Community Expert Disk1 has data. What do you think is missing? 3 hours ago, Duckysownyou said: had some file corruption What did you do about the corruption?
February 8, 20233 yr Author 55 minutes ago, trurl said: Disk1 has data. What do you think is missing? Couple hundred GB of videos 55 minutes ago, trurl said: What did you do about the corruption? Im not sure, it was gone after the array rebuild
February 8, 20233 yr Community Expert Rebuild can't delete files, parity doesn't know anything about files. What disk do you think the missing files were on? Did it actually say any disk was unmountable?
February 8, 20233 yr Community Expert 1 hour ago, Duckysownyou said: it informed me that the drive would be erased The only time it would have said "erased" is if you agreed to format a disk. Possibly one of the disks you weren't rebuilding was unmountable, you formatted it, and that is what happened to the missing files.
February 8, 20233 yr Community Expert 1 hour ago, Duckysownyou said: Disk 2,4,5 never really had anything on them I can understand disks 4,5 might not have been used yet, but usually disk2 would have gotten files before disk3. And now disk2 doesn't have files. Do you have earlier diagnostics?
February 8, 20233 yr Author 16 hours ago, trurl said: The only time it would have said "erased" is if you agreed to format a disk. Possibly one of the disks you weren't rebuilding was unmountable, you formatted it, and that is what happened to the missing files. gottcha, maybe that is what happened then. 16 hours ago, trurl said: I can understand disks 4,5 might not have been used yet, but usually disk2 would have gotten files before disk3. And now disk2 doesn't have files. Do you have earlier diagnostics? I do not have any earlier diagnostics sorry.
February 8, 20233 yr Author 16 hours ago, trurl said: The only time it would have said "erased" is if you agreed to format a disk. Possibly one of the disks you weren't rebuilding was unmountable, you formatted it, and that is what happened to the missing files. That has me thinking now. If I formatted a drive or deleted a file is that data instantly removed from parity?
February 8, 20233 yr 2 hours ago, Duckysownyou said: That has me thinking now. If I formatted a drive or deleted a file is that data instantly removed from parity? Yes, parity is updated realtime. That's why you need a versioned backup to recover from data corruption or deletion. Parity only rebuilds a drive exactly as it was when the drive was dropped. If there was data corruption, it will be rebuilt with the corruption. If parity was NOT in sync when the drive was dropped, the rebuilt drive will have corruption where it was out of sync. That's why periodic parity checks are important.
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.