Mirrored Cache Pool Showing 'Unmountable: No File System'

[techscholar]

After a reboot of my unRAID server I noticed my cache drives (2 x 1TB SSDs mirrored) are showing as 'Unmountable: No File System'. The array also immediately performed a parity check which passed without errors.

 

I found a post (by sniggil) with a similar issue to my own. A response from JorbeB pointed to the below post which I have followed to mount the cache drives individually and backed up the data from both drives onto a drive in my Unassigned Devices. Given they were mirrored I'm not sure if this was absolutely necessary, but I don't want to loose anything if at all possible.

To backup the drives I mounted the 1st cache drive on /x and the 2nd on /y then used the following commands to create a copy of the data:

rsync -aczvAXHS --progress /x /mnt/disks/UD_TempStorage/cache_d1_backup

rsync -aczvAXHS --progress /y /mnt/disks/UD_TempStorage/cache_d2_backup

 

Note: I don't know enough about rsysnc to come up with the above commands - full disclosure, I found them online!

I now have no clue on the process I need to follow to get the system back up and running correctly and are seeking some guidance. I am thinking something like:

1. Format the cache drives.
2. Copy the data from my Unassigned Device drive to the newly formatted cache drive(s).

 

I have included the Tools -> Diagnostics output for completeness.

 

Any information would be greatly appreciated.

 

Thanks in advance.

kratos-diagnostics-20220301-0048.zip

[JorgeB]

1 hour ago, techscholar said:

I am thinking something like:

1. Format the cache drives.
2. Copy the data from my Unassigned Device drive to the newly formatted cache drive(s).

That's it, and both backups you did should have the same data.

[techscholar]

Success! So I have the server back up and it looks to be working as it was prior to the "issue" with one exception. I have errors on my 2nd cache drive (refer attached image). I think that drive may be on its way out??? I better look at how I can undertake some diagnostics on the drive to get a definitive answer as the drive is currently still under warranty.

 

Another thing I noticed was a new section on the Main tab called Historical Devices (refer attached image). Does anyone know what this is and should I just delete these OR do I need to do something with this detail?

 

I thought I'd quickly jot down the main steps I had to go through. Hopefully it might be useful to someone else?

1. Mount the drive that is reporting as "Unmountable" (using the FAQ referenced in my previous post).
2. Backup all data on the drive to another drive (I used rsync. e.g. rsync -aczvAXHS --progress /source /target Note: I found that the source directory was created in the target directory with all of it files and folder structure).
3. Compare the backed up data with the original [optional] (I used rsync. e.g. rsync -n -avrc /source/ /target/source/).
4. Unmount the drive (e.g. umount /source).
5. Destroy data on the drive (my device was a SSD so I used blkdiscard /dev/sdX).
6. Format the drive via the unRAID GUI.
7. Copy all data back onto the cache drive (rsync -aczvAXHS --progress /target/source/ /mnt/cache).
8. Compare the restored files [optional] (rsync -n -avrc /target/source/ /mnt/cache/).
9. Reboot the unRAID server.

 

Edited March 2, 2022 by techscholar

[JorgeB]

20 minutes ago, techscholar said:

I have errors on my 2nd cache drive (refer attached image). I think that drive may be on its way out???

That's a SMART warning, might or note be serious, need the SMART report.

 

21 minutes ago, techscholar said:

Another thing I noticed was a new section on the Main tab called Historical Devices (refer attached image).

That's from the UD plugin, you can remove them from there, or toggle the historical devices button to not show then.

[ChatNoir]

19 minutes ago, techscholar said:

Another thing I noticed was a new section on the Main tab called Historical Devices (refer attached image). Does anyone know what this is and should I just delete these OR do I need to do something with this detail?

This is in the Unassigned Devices plugin. Certainly useful to manage plug and play devices that you use often for backup etc.

In you case, not so much. I think you can simply hit the X to remove them.

 

21 minutes ago, techscholar said:

I think that drive may be on its way out??? I better look at how I can undertake some diagnostics on the drive to get a definitive answer as the drive is currently still under warranty.

Difficult to say.

Attach your diagnostics to your next post so someone can look at it and provide an advice.

[techscholar]

 Tools -> Diagnostics output attached.

Performed a SMART extended self-test (SMART Report attached) - Passed. A good surprise.

 

kratos-diagnostics-20220303-0712.zip Samsung_SSD_870_EVO_1TB_S5Y2NJ0R111177Y-20220303-1854.txt.zip

[JorgeB]

Acknowledge current SMART attributes and keep monitoring, it's showing some issues but nothing fatal for now.

[techscholar]

Thanks for your guidance @JorgeB and @ChatNoir it is greatly appreciated.