Two drives unmountable, but can be read on other systems

[guythnick]

I have a big issue this morning I am hoping someone can help me with.  As you can see below there are two disks that are unmountable in Unraid.  This morning disk 4 was in an error state, so I swapped out the cable for this disk and proceeded to remove and re-add the drive so that it rebuilds from parity.  However, upon starting the array, Disk 1 was showing as missing. I rebooted my server, and it then shows as disabled.  The system went on to sync parity, and Disk 4 now shows green, yet unmountable.

 

I could accept HW failure and move on, but both of these disks when mounted in my USB enclosure on my Windows machine will show all files using Linux Reader. 

 

I have swapped postitions / cables / from LBA to on-board SATA, nothing has worked. Also want to note that when I start the array in maint mode and try to check the file system for this disk, it will just output this:

 

Phase 1 - find and verify superblock... superblock read failed, offset 0, size 524288, ag 0, rval -1 fatal error -- Input/output error

 

Is there anyway I can just force Unraid to mount these disks?  I don't understand how the file system is fully readable on another machine but not in Unraid. 

 

freenasmedia-diagnostics-20211220-1037.zip

[JorgeB]

Diags show disk4 is invalid, screenshot shows green, which is strange, in any case you started to rebuild disk4 with disk1 disable, which is not possible, but then canceled, so damage might not be that much, since both disks look healthy you can do a new config to re-configure the array, disk1 should immediately mount, disk4 may mount or not, it might a need a filesystem check.

[guythnick]

Yes, the diagnostic files were taken before the parity sync completed. When I downloaded the diagnostic they were both showing red.

I guess I will try doing a new config, but I am just worried I will lose data from both drives.  Maybe I will just try to figure out a way to get the files off of them in Windows first.

[JorgeB]

Data on disk1 should be all there, on disk4 there could be some data loss, depends for how long the rebuild ran, you should never have attempted a rebuild with another disk disabled and single parity.

[guythnick]

That is the problem, disk1 wasn't disabled until I started the array.  The system automatically started rebuilding at the same time.

[guythnick]

Parity is rebuilding and all files appear to be available.  Here is what I did:

* Stopped the array.

* Manually ran the below on the un-mountable disk

xfs_repair -L /dev/sdb1

           *I had to run this with -L as without it it would not run.

*Generate New Config with the same assignments.

 

After these steps it started the parity rebuild, and all the shares are still available.  So far, all the files seem to be there, but if there is any corruption I will just have to deal with it at this point.