Unraid v6.12.15

Array with 5 data and 2 parity disks, hybrid ZFS

Hey everyone. I had probably a SATA cable spontaneously fail and cause errors, by the time i noticed it it had already affected data written to a disk. ZFS scrub shows as source of errors "disk2/Sync: <0x0>" which from what i've read seems to indicate errors in the metadata or else it would show actual filenames.

It only seems to affect this one share so after swapping cables and verifying no more errors occur through a full parity check, i tried wiping it. However, both midnight commander and krusader can't delete a few folders / files. Looking into those not through user shares (where they don't show up) but through disk2 directly, there seem to be a handful (maybe 10) of corrupted files that can't be deleted by either MC nor krusader. And their parent folders can't be deleted either. You can see one example of an undeletable file in the attachments

I don't have the spare disks for a full backup and set up the whole NAS from scratch (90TB), so i'm hoping i can somehow just remove and re-set up this one share (backups of that have been made), but stuck at this deletion step because you can't delete shares as long as they're not fully empty.

So now not sure how to proceed from here - is there any way to remove these files / folders when MC and Krusader fail, or otherwise how to nuke the share so that share can be set up from scratch again? Something else to do in this situation, without being able to do a full wipe of the NAS?

Thanks in advance for any pointers~

Cable problems should never cause data corruption unless the device/controller has bad firmware, so it may also be good to run memtest.

The only way to fix that is to back up what you can and reformat that disk. You don't need to back up all the data, just that disk (disk2).

Okay, yeah getting the spare storage for a backup of a full disk isn't trivial but doable so i'll try that. Thanks.

When you say reformat the disk, do you mean using the erase function in Unraid in the disk menu? Never had to do this before.

And i suspected the RAM as well and did run memtest over night / for a good dozen passes or so which turned out fine. So either it was a cable, or otherwise a weird temporary issue that has not shown up since swapping SATA cables for a full parity check and many memtest passes.

12 hours ago, river_system said:

When you say reformat the disk, do you mean using the erase function in Unraid in the disk menu?

You can do that, need to start the array in maintenance mode for the erase disk option to be available.