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BTRFS cache pool of 2 wont mount.

Featured Replies

Hello, I have been searching for a solution for my problem for quite some time. My cache pool of two devices will not mount after reboot.

 

The error listed is " Unmountable: Unsupported or no file system".

 

I have tried to run "mount -o rescue=all,ro /dev/sdg1 /temp" with the error given as: "mount: /temp: special device /dev/sdg1 does not exist"

If anyone would be able to help me figure out what may be the issue I would appreciate it. 

image.thumb.png.9a1adfe51cbdc3d585d12af0a8aba3b3.png

tower-diagnostics-20240516-1451.zip

Edited by Markus G

Solved by JorgeB

  • Community Expert

Please post output of:

btrfs fi show

 

  • Author

Thank you for the quick response. 

 

Label: none  uuid: af20d1aa-8c85-4763-bc7b-7e006bd5d28f
        Total devices 1 FS bytes used 360.00KiB
        devid    1 size 20.00GiB used 536.00MiB path /dev/loop2

Label: none  uuid: 45b84021-bb40-449d-8611-1718beef11d8
        Total devices 1 FS bytes used 412.00KiB
        devid    1 size 1.00GiB used 126.38MiB path /dev/loop3

  • Community Expert

Are you sure the pool was btrfs? No btrfs filesystem is being detected there, post the output of:

blkid

and

fdisk -l /dev/sdf

 

  • Author

I am not sure If it was configured as btrfs. 

 

root@server:~# blkid
/dev/sda1: LABEL_FATBOOT="UNRAID" LABEL="UNRAID" UUID="70E8-E43D" BLOCK_SIZE="512" TYPE="vfat" PARTUUID="e761811e-01"
/dev/loop1: TYPE="squashfs"
/dev/sdd1: UUID="7491c33f-9a47-4d86-a433-fefcb05460d1" BLOCK_SIZE="512" TYPE="xfs" PARTUUID="3e0e5162-01b5-47fc-af19-f632aeb002c0"
/dev/md2p1: UUID="6a042d73-4288-4ba5-a4bc-60fd80f0d90c" BLOCK_SIZE="512" TYPE="xfs"
/dev/sdm1: UUID="1bbe4c36-6991-4bb0-b03f-66cbf2a070b9" BLOCK_SIZE="512" TYPE="xfs"
/dev/sdb1: UUID="2d4ca56c-45a5-4bb0-901e-a2c096c99749" BLOCK_SIZE="512" TYPE="xfs" PARTUUID="0ee027fb-3374-4b8a-a4aa-316d63236d20"
/dev/md5p1: UUID="23b0cb58-8711-4c9b-aff3-faaa94ee862b" BLOCK_SIZE="4096" TYPE="xfs"
/dev/sdk1: UUID="23b0cb58-8711-4c9b-aff3-faaa94ee862b" BLOCK_SIZE="4096" TYPE="xfs" PARTUUID="8c0247df-0ce8-45cc-a7be-f885d42df9e4"
/dev/sdi1: UUID="bd9860f6-0012-4c23-babf-a6d6e0c87b1e" BLOCK_SIZE="512" TYPE="xfs" PARTUUID="ead8dadf-665a-427d-8ee9-60f8cf4bc2fe"
/dev/md1p1: UUID="2d4ca56c-45a5-4bb0-901e-a2c096c99749" BLOCK_SIZE="512" TYPE="xfs"
/dev/md4p1: UUID="661713c1-2803-4a34-afaa-2af863d73d1e" BLOCK_SIZE="512" TYPE="xfs"
/dev/loop0: TYPE="squashfs"
/dev/sde1: UUID="661713c1-2803-4a34-afaa-2af863d73d1e" BLOCK_SIZE="512" TYPE="xfs" PARTUUID="5ccf249c-997e-4b1a-9edd-080c652f8fb2"
/dev/md7p1: UUID="1bbe4c36-6991-4bb0-b03f-66cbf2a070b9" BLOCK_SIZE="512" TYPE="xfs"
/dev/sdc1: UUID="6a042d73-4288-4ba5-a4bc-60fd80f0d90c" BLOCK_SIZE="512" TYPE="xfs" PARTUUID="7ed032ea-85a7-4979-8ff0-2d57f9080918"
/dev/sdl1: UUID="d058bf79-5bfb-4caf-9a48-2c8e433c9e06" BLOCK_SIZE="4096" TYPE="xfs" PARTUUID="88fae84c-783b-4138-967b-1b1a9c0a8722"
/dev/md3p1: UUID="7491c33f-9a47-4d86-a433-fefcb05460d1" BLOCK_SIZE="512" TYPE="xfs"
/dev/md6p1: UUID="d058bf79-5bfb-4caf-9a48-2c8e433c9e06" BLOCK_SIZE="4096" TYPE="xfs"
/dev/loop2: UUID="af20d1aa-8c85-4763-bc7b-7e006bd5d28f" UUID_SUB="6cb90d2c-09e2-482d-a55f-5c0f1532a256" BLOCK_SIZE="4096" TYPE="btrfs"
/dev/loop3: UUID="45b84021-bb40-449d-8611-1718beef11d8" UUID_SUB="549d35e8-87f7-4dd8-a6c9-00e72c67c260" BLOCK_SIZE="4096" TYPE="btrfs"
/dev/sdj1: PARTUUID="6c3e04a0-5dce-418e-ae74-47f362c3956f"
root@server:~# fdisk -l /dev/sdf
Disk /dev/sdf: 931.51 GiB, 1000204886016 bytes, 1953525168 sectors
Disk model: WD Blue SA510 2.
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
 

  • Community Expert

Device doesn't have a partition, something/someone wiped it, type:

 

sfdisk /dev/sdf

then type

2048

and hit Enter, post the results of that

  • Author

 

root@server:~# sfdisk /dev/sdf

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/sdf: 931.51 GiB, 1000204886016 bytes, 1953525168 sectors
Disk model: WD Blue SA510 2.
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 0x9652982f.
Created a new partition 1 of type 'Linux' and of size 931.5 GiB.
Partition #1 contains a btrfs signature.

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

 

 

I have not selected an option for the Y/N question.  

  • Community Expert

Type N and hit Enter to keep the signature, then type write and hit Enter, after that post again output of

btrfs fi show

 

  • Author

Do you want to remove the signature? [Y]es/[N]o: n
   /dev/sdf1 :         2048   1953525167 (931.5G) Linux
/dev/sdf2: write

New situation:
Disklabel type: dos
Disk identifier: 0x9652982f

Device     Boot Start        End    Sectors   Size Id Type
/dev/sdf1        2048 1953525167 1953523120 931.5G 83 Linux

The partition table has been altered.
Calling ioctl() to re-read partition table.
Syncing disks.
root@server:~# btrfs fi show
Label: none  uuid: af20d1aa-8c85-4763-bc7b-7e006bd5d28f
        Total devices 1 FS bytes used 360.00KiB
        devid    1 size 20.00GiB used 536.00MiB path /dev/loop2

Label: none  uuid: 45b84021-bb40-449d-8611-1718beef11d8
        Total devices 1 FS bytes used 412.00KiB
        devid    1 size 1.00GiB used 126.38MiB path /dev/loop3

warning, device 3 is missing
Label: none  uuid: 8ea836b8-5eef-434c-842b-38d7b512bf3f
        Total devices 2 FS bytes used 153.49GiB
        devid    4 size 931.51GiB used 157.03GiB path /dev/sdf1
        *** Some devices missing

 

 

  • Community Expert

Now repeat the sfisk commands for the other pool device, /dev/sdg, but only write the new partition layout if it also finds a btrfs signature, when that's done post again btrfs fi show

  • Author

Completed as instructed. I did find a btrfs signature on sdg and did write the partition.

 

root@server:~# btrfs fi show
Label: none  uuid: af20d1aa-8c85-4763-bc7b-7e006bd5d28f
        Total devices 1 FS bytes used 360.00KiB
        devid    1 size 20.00GiB used 536.00MiB path /dev/loop2

Label: none  uuid: 45b84021-bb40-449d-8611-1718beef11d8
        Total devices 1 FS bytes used 412.00KiB
        devid    1 size 1.00GiB used 126.38MiB path /dev/loop3

Label: none  uuid: 8ea836b8-5eef-434c-842b-38d7b512bf3f
        Total devices 2 FS bytes used 153.49GiB
        devid    3 size 931.51GiB used 157.03GiB path /dev/sdg1
        devid    4 size 931.51GiB used 157.03GiB path /dev/sdf1

 

 

  • Community Expert
  • Solution

Re-start the array, pool should mount now, if it doesn't post new diags.

  • Author

You are a legend! The pool has started. 

As you know, I must now remit my engineering degree to you. 

 

Thank you for your help. 

 

 

Edited by Markus G

  • Community Expert

You're welcome, I assume you have no idea of what happened to the partitions? Just a normal reboot and this happened?

 

 

  • Author

It was odd, plex was flaking out so I rebooted and the drives failed to mount. 

I'm not sure what happened. 

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