I had two drives fail. I precleared two new disks that were mounted as UD. I then stopped the array, mounted those drives in the failed drives slots and started the array. I did not check the box for formatting the drives and then format. They show as unmountable filesystem, but the rebuild ran completely and per the read/write data it seems like it rebuilt that data and completed. But, the drives still show unmountable next to them and have the format option at the bottom. I thought Pre-clear formatted them already. How do i resolve this? Ideally without running a whole new rebuild.

tvserver01-diagnostics-20230818-2048.zip

If any disks are unmountable before rebuilding they will remain unmountable during and after it finishes rebuilding, check filesystem on both disks (without -n).

6 hours ago, scuppasteve said:

I thought Pre-clear formatted them already.

It does not - it creates the correct partition structure and then writes all zeroes to the Unraid partition so it can be added to the array without affecting parity.   Note that pre-clear is only REQUIRED when adding new drives AND you want to first stress test them.  A rebuild overwrites every sector on the drive so the fact it has been pre-cleared is irrelevant.

 

FYI:  The correct handling of unmountable drives is covered here in the Unraid online documentation.

 

Well, i checked the drives and there was no file system so i formatted the drives and now when i started up it seems like all that data is gone and i am guessing gone from parity? I immediately stopped the array when that was the case, is there any way re-run the rebuild process?

2 hours ago, scuppasteve said:

Well, i checked the drives and there was no file system so i formatted the drives and now when i started up it seems like all that data is gone and i am guessing gone from parity? I immediately stopped the array when that was the case, is there any way re-run the rebuild process?

Formatting a drive is NEVER part of a data recovery process (you would have got a warning about this when you selected the format option).    The format would have created an empty file system on the drive and updated parity to reflect this.

 

You may be able to recover some (most) of the data off the drive using file recovery software such as UFS Explorer on Windows.

Well, i think i have finally hit my point of no return for Unraid and i am going to find a different solution. The fact that after 5 years, it still is incredibly user unfriendly with a guides that are either out of date or are just a massive blog of text without a clear process on how to resolve issues. Thanks for taking the time to try to assist. I have never lost more data than i have with Unraid.