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Cache Disk Unmountable?

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Hello all!

 

So I recently had a cache drive failure, and replaced it (maybe 3 weeks ago, tops) with a brand new SSD. I woke up this morning and noticed my Docker containers were down, so I went to investigate. I tried restarting the container in question, and noticed some errors while it was trying to start. I rebooted the server, and once it came up I saw that the cache drive was "unmountable".

 

Since I'm on unraid 6.x, I stopped the array, started in maintenance mode, and ran a check (-nv), followed by another check (-v). It's weird it seems like the process was successful as no errors were reported (some files seem to have been moved to lost+found), but I'm still not able to mount the drive. Here's the tail end of the log from the check I ran.

 

Phase 7 - verify and correct link counts...
resetting inode 816629359 nlinks from 1 to 2
resetting inode 2032652 nlinks from 2 to 3
resetting inode 3164097 nlinks from 2 to 1
Maximum metadata LSN (48:72667) is ahead of log (47:440994).
Format log to cycle 51.

        XFS_REPAIR Summary    Mon Feb 20 11:02:02 2023

Phase		Start		End		Duration
Phase 1:	02/20 11:01:59	02/20 11:01:59
Phase 2:	02/20 11:01:59	02/20 11:01:59
Phase 3:	02/20 11:01:59	02/20 11:02:00	1 second
Phase 4:	02/20 11:02:00	02/20 11:02:00
Phase 5:	02/20 11:02:00	02/20 11:02:00
Phase 6:	02/20 11:02:00	02/20 11:02:01	1 second
Phase 7:	02/20 11:02:01	02/20 11:02:01

 

The full logs are really long and I'm not sure how useful they are for anyone offering help, so let me know if I should include those. There really isn't a next steps option on the page besides a full redo, is that what's required here? https://wiki.unraid.net/Check_Disk_Filesystems#Redoing_a_drive_formatted_with_XFS

 

Kind of a bummer since I just went through this process of restoring my app data, but I just want to make sure I don't have any more options before I move forward. Thanks!!

  • Community Expert

Please post the diags after array start.

  • Author
11 minutes ago, JorgeB said:

Please post the diags after array start.

 Appreciate the reply – just stopped the array (was in maintenance mode), started it, and pulled the diagnostics. See attached.

tayshserve-diagnostics-20230220-1133.zip

  • Community Expert
1 hour ago, tayshserve said:

full logs are really long

zip and post

  • Author

I was being dramatic and quite frankly, lazy. I attached the full output from the check in a txt file, it's only 300kb.

 

Thanks for the nudge @trurl

check_logs.txt

  • Community Expert

Did you do the check from the webUI or the command line? Easy to get the command wrong.

  • Author
15 minutes ago, trurl said:

Did you do the check from the webUI or the command line? Easy to get the command wrong.

I ran it straight from the GUI – first I ran it with `-nv` then I ran it with just `-v` after that. 

  • Author

Honestly no real reason. Before my cache drive decided to die I had like 300+ days of uptime – things were pretty stable so I just didn't want to mess with it.

 

Before I got about formatting this cache drive and all of that – should I try updating and run the check again and see what happens?

  • Community Expert
1 minute ago, tayshserve said:

try updating and run the check again and see what happens?

Worth a try

  • Author
14 minutes ago, trurl said:

Worth a try

Still comes out as unmountable – I'll attach the logs from the check again. Looking like I'll just have to format the drive and deal with any potential fallout? (almost always plex DB corruption lol)

 

check_logs_new.txt

  • Community Expert

Might be worth seeing the diagnostics in case there is something going on at the disk I/O level interfering with this.

  • Author

Here's the diagnostics one more time! Is there any way to get files off of this drive before I format it (assuming I'm gonna have to go that route)? Wondering if I can attempt to save a couple of databases – I feel like whenever this happens I have to reconfigure Plex and Home Assistant as their database seems to corrupt and start from scratch.

tayshserve-diagnostics-20230220-1315.zip

  • Community Expert
2 minutes ago, tayshserve said:

whenever this happens

You have CA Backup plugin installed. Have you tried restoring appdata?

  • Author

Funny story – this is the 3rd time I've had some type of cache drive related issue. The first time I had no backup – learned my lesson and backed up my entire appdata directory to Backblaze b2 via Duplicati. The second time, I restored from the Backblaze backup.. and it took FOREVER. Like 20 hours or so. 

 

Anyway, I decided to use CA Backup and noticed I could ignore a folder.. so I ignored all the heavy media folders within Plex. Turns out you can't ignore just a child folder? Or – if you can, I didn't do it properly. Anyway, I now specifically have no backup for plex! 

 

So hopefully whatever is on the array for Plex isn't corrupt!

  • Community Expert

Currently, your default shares

https://wiki.unraid.net/Manual/Shares#Default_Shares

are on the array.

 

Since you have Docker and VM Manager enabled, and no cache, it had to recreate these from scratch on the array.

 

Normally, you want the default shares cache:prefer so Docker/VM performance isn't impacted by parity, and so array disks can spin down since these files are always open.

 

Maybe you set these to cache:yes because you were having cache problems, but appdata is actually set cache:only currently. I would expect any attempt to write to appdata wouldn't succeed since there is no cache for it to write to. The appdata on the array must have been there from before.

 

What folders are currently in appdata?

 

You should install Dynamix File Manager plugin, it will make it a lot easier to work with your user shares and disks directly on the server.

  • Author
3 minutes ago, trurl said:

What folders are currently in appdata?

 

You should install Dynamix File Manager plugin, it will make it a lot easier to work with your user shares and disks directly on the server.

Going to install that now.. I currently have all the folder I would suspect on the array – just seems weird the last modified dates are super old for everything. Screenshot attached of the folders.

 

So yeah currently my appdata folder is set to "Only : Cache" which I'm guessing is incorrect, and means that my appdata folder never gets copied back to the array. So the only way to remedy my Plex situation (all others are backed up) would be to potentially get the files off the cache before formatting? Is that even possible?

Screen Shot 2023-02-20 at 1.40.28 PM.png

  • Community Expert
9 minutes ago, tayshserve said:

the last modified dates are super old for everything

If you didn't have the default shares as cache:prefer, then they probably wouldn't have been recreated. If these shares were cache:no or cache:yes, they were probably already on the array.

18 minutes ago, trurl said:

Normally, you want the default shares cache:prefer so Docker/VM performance isn't impacted by parity, and so array disks can spin down since these files are always open.

 

 

  • Community Expert
12 minutes ago, tayshserve said:

get the files off the cache before formatting?

There are other file recovery applications, UFS Explorer is often mentioned since it supports Unraid filesystems. Whether it can succeed when xfsprogs couldn't?

  • Author
1 hour ago, trurl said:

There are other file recovery applications, UFS Explorer is often mentioned since it supports Unraid filesystems. Whether it can succeed when xfsprogs couldn't?

Yeah – so this is probably good advice so I don't waste my time.. Especially since the Plex database can be rebuilt. It's just annoying telling all my family they need to repin all of their content.

 

I'm just gonna format and get myself back on track, plex should be easy enough to get going again.

 

I want to say, thanks for sticking with this thread @trurland shout out to @JorgeBwho has also helped me directly before and countless times before by just being the solution to other issues on the boards.

  • Author

@trurl hmm more interesting developments – now it appears I'm unable to format the cache drive. It just gets stuck in the "Formatting" state. I feel this typically takes 5 seconds or so and the UI updates that the process is done.

  • Author

I'm not sure what's going on.. I've tried a few different things. Tried to unassign the device, start the array back up, stop the array, reassign the device.. no luck. I also tried deleting the pool and starting from scratch, nothing. Seems like something is going on with this disk? Diags attached, thanks!

tayshserve-diagnostics-20230220-1641.zip

  • Community Expert

I don't know, syslog seems like it should have worked. Run an extended self-test on it while you wait some hours to see if @JorgeBhas any ideas.

  • Author

More lessons learned from past failures – when I bought my replacement SSD I actually bought 2 to have 1 as a back up. I popped that into my server and was able to remove the corrupt drive, format the new backup drive I had, and add that as the cache. I now have the corrupt drive as an unassigned device, however I'm still unable to format it. I suppose it could be the cable the original drive is using? 

 

I'm back up and running but would still like to understand what happened here so I can prevent it in the future. Thanks again, really appreciate your help as our whole house runs on this server haha.

Edited by tayshserve

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