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(SOLVED) Cache pool: "Unmountable: Unsupported or no file system"

Featured Replies

I hope someone can help, please?

 

I woke up this morning to find my cache pool of 2 devices were no longer mounted.

 

I've tried stopping the array, un-assign both cache devices. Start array. Stop array, reassign both cache devices. Start array. = Same error.

 

Please advice!

 

eXIG1O9.png

 

 

box-diagnostics-20241020-1546.zip

Edited by Xenu

Solved by JorgeB

  • Community Expert

Pool is complaining of a missing device, post the output from

btrfs fi show

 

  • Author

Thank you for the reply.

 

This is the response:

root@box:~# btrfs fi show
Label: none  uuid: 94418e24-71a8-4933-a795-612a5f71ebf5
        Total devices 1 FS bytes used 412.00KiB
        devid    1 size 2.00GiB used 228.75MiB path /dev/loop2

warning, device 2 is missing
warning, device 2 is missing
ERROR: cannot read chunk root
Label: none  uuid: adb84329-04d6-471b-afbd-2443872bcda4
        Total devices 2 FS bytes used 1.88TiB
        devid    1 size 1.82TiB used 1.82TiB path /dev/sdi1
        *** Some devices missing

 

This is with the array online and both cache drives assigned.

  • Community Expert

Any idea why there's a missing device? Did you try replacing or removing cache2 before?

  • Author

No idea. Nothing was tinkered with/changed, just happened overnight.

Checked cables, all fine there.

  • Community Expert

Stop the array and type and post the output from

fdisk -l /dev/sdi

and

fdisk -l /dev/sdd

 

  • Author
3 minutes ago, JorgeB said:

Stop the array and type and post the output from

fdisk -l /dev/sdi

and

fdisk -l /dev/sdd

 

root@box:~# fdisk -l /dev/sdi
Disk /dev/sdi: 1.82 TiB, 2000398934016 bytes, 3907029168 sectors
Disk model: CT2000MX500SSD1 
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disklabel type: dos
Disk identifier: 0x00000000

Device     Boot Start        End    Sectors  Size Id Type
/dev/sdi1        2048 3907029167 3907027120  1.8T 83 Linux
root@box:~# fdisk -l /dev/sdd
Disk /dev/sdd: 476.94 GiB, 512110190592 bytes, 1000215216 sectors
Disk model: Tech            
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes

 

I notice the two drives are now also showing under historical devices:

zURWeQh.png

  • Community Expert

cache2 is missing the partition, type

sfdisk /dev/sdd

then type 2048 and ENTER and post the output from that, without typing anything else

  • Author
1 minute ago, JorgeB said:

cache2 is missing the partition, type

sfdisk /dev/sdd

then type 2048 and ENTER and post the output from that, without typing anything else

Thank you.

root@box:~# sfdisk /dev/sdd

Welcome to sfdisk (util-linux 2.38.1).
Changes will remain in memory only, until you decide to write them.
Be careful before using the write command.

Checking that no-one is using this disk right now ... OK

Disk /dev/sdd: 476.94 GiB, 512110190592 bytes, 1000215216 sectors
Disk model: Tech            
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes

sfdisk is going to create a new 'dos' disk label.
Use 'label: <name>' before you define a first partition
to override the default.

Type 'help' to get more information.

>>> 2048
Created a new DOS disklabel with disk identifier 0x7ad5d360.
Created a new partition 1 of type 'Linux' and of size 476.9 GiB.
   /dev/sdd1 :         2048   1000215215 (476.9G) Linux
/dev/sdd2: 

Looks like it's awaiting another input?

  • Community Expert

Hit CTRL + C to abort, then repeat but use 64 instead of 2048, and post output of that.

  • Author
28 minutes ago, JorgeB said:

Hit CTRL + C to abort, then repeat but use 64 instead of 2048, and post output of that.

root@box:~# sfdisk /dev/sdd

Welcome to sfdisk (util-linux 2.38.1).
Changes will remain in memory only, until you decide to write them.
Be careful before using the write command.

Checking that no-one is using this disk right now ... OK

Disk /dev/sdd: 476.94 GiB, 512110190592 bytes, 1000215216 sectors
Disk model: Tech            
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes

sfdisk is going to create a new 'dos' disk label.
Use 'label: <name>' before you define a first partition
to override the default.

Type 'help' to get more information.

>>> 64
Created a new DOS disklabel with disk identifier 0xcc0341ce.
Created a new partition 1 of type 'Linux' and of size 476.9 GiB.
Partition #1 contains a btrfs signature.

Do you want to remove the signature? [Y]es/[N]o: 

 

  • Community Expert
  • Solution

Type No and Enter to keep the signature

Then type write and Enter to save the changes

Output of

btrfs fi show

 

  • Author
15 minutes ago, JorgeB said:

Type No and Enter to keep the signature

Then type write and Enter to save the changes

Output of

btrfs fi show

 

Do you want to remove the signature? [Y]es/[N]o: N
   /dev/sdd1 :           64   1000215215 (476.9G) Linux
/dev/sdd2: write

New situation:
Disklabel type: dos
Disk identifier: 0xcc0341ce

Device     Boot Start        End    Sectors   Size Id Type
/dev/sdd1          64 1000215215 1000215152 476.9G 83 Linux

The partition table has been altered.
Calling ioctl() to re-read partition table.
Syncing disks.
root@box:~# btrfs fi show
Label: none  uuid: adb84329-04d6-471b-afbd-2443872bcda4
        Total devices 2 FS bytes used 1.88TiB
        devid    1 size 1.82TiB used 1.82TiB path /dev/sdi1
        devid    2 size 476.94GiB used 476.94GiB path /dev/sdd1

 

  • Community Expert

Now start the array and post new diags.

  • Author
13 minutes ago, JorgeB said:

Now start the array and post new diags.

You genius, functioning again! Thank you! I manually stopped Docker in case there's any ongoing issues.

box-diagnostics-20241021-1609.zip

Edited by Xenu

  • Community Expert

There's still the question of what happened to the partition, but maybe it was a fluke, take the opportunity to update your backups if needed.

  • Author
Just now, JorgeB said:

There's still the question of what happened to the partition, but maybe it was a fluke, take the opportunity to update your backups if needed.

Many many thanks, Jorge! Popped you a little beer money your way!

  • Xenu changed the title to (SOLVED) Cache pool: "Unmountable: Unsupported or no file system"
  • Community Expert

Thanks! There's also data corruption being detected by btrfs, you should run a scrub.

  • Author
4 minutes ago, JorgeB said:

Thanks! There's also data corruption being detected by btrfs, you should run a scrub.

Running it now, already started making corrections. Thank you again!

  • Author
20 hours ago, JorgeB said:

Thanks! There's also data corruption being detected by btrfs, you should run a scrub.

Hello Jorge, thank you again! I left the scrub running overnight and immediately it was finding bad bits. It did however abort the scrub by itself overnight and attempting the scrub again simply does nothing (pressing the srub button had the page pending for a second or two, but nothing more happened). I powed off the server.

 

Booting it back up today, the cache pool has also reverted to how it looked at the start of this thread. 

 

I had a go at bringing the cache pool back online using your steps above, as the terminal response from each step was the same, however after reaching this step:

- I'm presented with this:

 

root@box:~# btrfs fi show
Label: none  uuid: 94418e24-71a8-4933-a795-612a5f71ebf5
        Total devices 1 FS bytes used 412.00KiB
        devid    1 size 2.00GiB used 228.75MiB path /dev/loop2

warning, device 2 is missing
warning, device 2 is missing
ERROR: cannot read chunk root
Label: none  uuid: adb84329-04d6-471b-afbd-2443872bcda4
        Total devices 2 FS bytes used 1.88TiB
        devid    1 size 1.82TiB used 1.82TiB path /dev/sdi1
        *** Some devices missing

 

Am I right to assume one of the drives needs replacing, as it's damaged/on it way out? Is there any way to identify what drive of the two might be the cause? And if so, is there anyway to shift the cache from one drive onto the other, or both cache drives content onto the non-cache drives until I can replace the cache drives?

 

Let me know if you feel I need to make a new thread for this!

box-diagnostics-20241022-1236.zip

Edited by Xenu

  • Community Expert

Looks like cache2 lost the partition again, this is not normal, was the device always connect with USB? Some USB bridges can cause strange issues.

 

In the meantime post the output from

 

fdisk -l /dev/sdd

 

  • Author
1 hour ago, JorgeB said:

Looks like cache2 lost the partition again, this is not normal, was the device always connect with USB? Some USB bridges can cause strange issues.

 

In the meantime post the output from

 

fdisk -l /dev/sdd

 

Thank you again for your time!

 

root@box:~# fdisk -l /dev/sdd
Disk /dev/sdd: 476.94 GiB, 512110190592 bytes, 1000215216 sectors
Disk model: Tech            
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes

 

Yes, one of the drives has always been connected via USB. I've been meaning to migrate back to one cache drive, internal SSD. If it's the USB one that's causing problems/damaged, would you be able to offer advice on how to migrate the data over and remove the USB drive from the pool, please? If I can get the array back online, I'll gladly just moved everything off the cache for time being.

Edited by Xenu

  • Community Expert

Type

sfdisk /dev/sdd

then type 64 and Enter and post the results

  • Author
22 minutes ago, JorgeB said:

Type

sfdisk /dev/sdd

then type 64 and Enter and post the results

root@box:~# sfdisk /dev/sdd

Welcome to sfdisk (util-linux 2.38.1).
Changes will remain in memory only, until you decide to write them.
Be careful before using the write command.

Checking that no-one is using this disk right now ... OK

Disk /dev/sdd: 476.94 GiB, 512110190592 bytes, 1000215216 sectors
Disk model: Tech            
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes

sfdisk is going to create a new 'dos' disk label.
Use 'label: <name>' before you define a first partition
to override the default.

Type 'help' to get more information.

>>> 

 

  • Community Expert
47 minutes ago, JorgeB said:

then type 64 and Enter and post the results

 

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