Adrian Dymorz

Creating a copy of the data and adding the devices to a new pool did work out flawlessly. Not sure about the root cause of the issue. That will probably remain an unsolved mystery.

I currently run "btrfs restore -d /dev/sdb1 /mnt/user/btrfs_restore/" to have a copy of the data before I do anything else. After that I am going to try to add the devices to a new pool. Thanks for your help! Is the link posted on the Unraid Community Rockstars page still valid?

Output of "sfdisk /dev/sdc" and the inputs "64", "N" and "write": 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/sdc: 465.76 GiB, 500107862016 bytes, 976773168 sectors Disk model: WDC WDS500G2B0A 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 0xf84ac41d. Created a new partition 1 of type 'Linux' and of size 465.8 GiB. Partition #1 contains a btrfs signature. Do you want to remove the signature? [Y]es/[N]o: N /dev/sdc1 : 64 976773167 (465.8G) Linux /dev/sdc2: write New situation: Disklabel type: dos Disk identifier: 0xf84ac41d Device Boot Start End Sectors Size Id Type /dev/sdc1 64 976773167 976773104 465.8G 83 Linux The partition table has been altered. Calling ioctl() to re-read partition table. Syncing disks. Output of "btrfs fi show": Label: none uuid: ed9ea52f-f8c5-40d9-9814-16f41b39251d Total devices 2 FS bytes used 35.00GiB devid 1 size 1.82TiB used 37.01GiB path /dev/nvme0n1p1 devid 2 size 1.82TiB used 37.01GiB path /dev/nvme1n1p1 Label: none uuid: fb0b5703-1252-43c3-8ee5-d49187894ad9 Total devices 1 FS bytes used 14.90MiB devid 1 size 35.00GiB used 1.52GiB path /dev/loop2 Label: none uuid: c8d7555b-394a-4039-9ea1-ddeaa04a6785 Total devices 1 FS bytes used 440.00KiB devid 1 size 1.00GiB used 126.38MiB path /dev/loop3 Label: none uuid: b7d22b34-fe12-4ec1-aa33-cadfd0a480e4 Total devices 2 FS bytes used 380.41GiB devid 1 size 465.76GiB used 424.00GiB path /dev/sdb1 devid 2 size 465.76GiB used 423.03GiB path /dev/sdc1

>>> 64 Created a new DOS disklabel with disk identifier 0x9a67f18e. Created a new partition 1 of type 'Linux' and of size 465.8 GiB. Partition #1 contains a btrfs signature. Do you want to remove the signature? [Y]es/[N]o:

"sfdisk /dev/sdc" returns 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/sdc: 465.76 GiB, 500107862016 bytes, 976773168 sectors Disk model: WDC WDS500G2B0A 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" as input returned: Created a new DOS disklabel with disk identifier 0xf50eb252. Created a new partition 1 of type 'Linux' and of size 465.8 GiB. /dev/sdc1 : 2048 976773167 (465.8G) Linux Now it is waiting for more input: /dev/sdc2:

"btrfs fi show" returns Label: none uuid: ed9ea52f-f8c5-40d9-9814-16f41b39251d Total devices 2 FS bytes used 35.00GiB devid 1 size 1.82TiB used 37.01GiB path /dev/nvme0n1p1 devid 2 size 1.82TiB used 37.01GiB path /dev/nvme1n1p1 Label: none uuid: fb0b5703-1252-43c3-8ee5-d49187894ad9 Total devices 1 FS bytes used 14.90MiB devid 1 size 35.00GiB used 1.52GiB path /dev/loop2 Label: none uuid: c8d7555b-394a-4039-9ea1-ddeaa04a6785 Total devices 1 FS bytes used 440.00KiB devid 1 size 1.00GiB used 126.38MiB path /dev/loop3 warning, device 2 is missing ERROR: cannot read chunk root Label: none uuid: b7d22b34-fe12-4ec1-aa33-cadfd0a480e4 Total devices 2 FS bytes used 380.41GiB devid 1 size 465.76GiB used 424.00GiB path /dev/sdb1 *** Some devices missing Yes, sdb and sdc were the original pool members.

I did reboot because that is what sometimes helps too.

I tried to replace the cache devices by bigger and faster ones. For this I tried to follow to procedure described in the Unraid 6 FAQ. Now I am unable to access the data on the cache drives. What I did trying to replace the drive 1. Add the two new SSDs to the system 2. Stop the array 3. Replace the device in the pool 4. Start the array 5. I then saw the error "Unmountable: Unsupported or no file system" Trying to fix it, I did the following: 1. Stop the array 2. Remove the newly added device from the pool 3. I still got the error "Unmountable: Unsupported or no file system" Now I am trying to restore the data from the cache drive What I see in the UI currently: Overview over devices ("ls -la /dev/sd*"): brw-rw---- 1 root plugdev 8, 0 Feb 27 12:05 /dev/sda brw-rw---- 1 root plugdev 8, 1 Feb 27 12:05 /dev/sda1 brw-rw---- 1 root disk 8, 16 Feb 27 22:36 /dev/sdb brw-rw---- 1 root disk 8, 17 Feb 27 22:46 /dev/sdb1 brw-rw---- 1 root disk 8, 32 Feb 27 22:35 /dev/sdc brw-rw---- 1 root disk 8, 48 Feb 27 12:05 /dev/sdd brw-rw---- 1 root disk 8, 49 Feb 27 12:05 /dev/sdd1 brw-rw---- 1 root disk 8, 64 Feb 27 12:05 /dev/sde brw-rw---- 1 root disk 8, 65 Feb 27 12:05 /dev/sde1 brw-rw---- 1 root disk 8, 80 Feb 27 12:05 /dev/sdf brw-rw---- 1 root disk 8, 81 Feb 27 12:05 /dev/sdf1 Note: There is no /dev/sdc1 Trying to run "btrfs restore -d /dev/sdb1 /mnt/user/btrfs_restore/" shows: warning, device 2 is missing bad tree block 386624946176, bytenr mismatch, want=386624946176, have=0 ERROR: cannot read chunk root Could not open root, trying backup super warning, device 2 is missing bad tree block 386624946176, bytenr mismatch, want=386624946176, have=0 ERROR: cannot read chunk root Could not open root, trying backup super warning, device 2 is missing bad tree block 386624946176, bytenr mismatch, want=386624946176, have=0 ERROR: cannot read chunk root Could not open root, trying backup super Trying to run "btrfs rescue zero-log /dev/sdb1" shows: warning, device 2 is missing ERROR: cannot read chunk root ERROR: could not open ctree Trying to run "btrfs-select-super -s 1 /dev/sdb1" shows: warning, device 2 is missing ERROR: cannot read chunk root ERROR: could not open ctree Trying to run "btrfs-select-super -s 1 /dev/sdb1" shows: Opening filesystem to check... warning, device 2 is missing bad tree block 386624946176, bytenr mismatch, want=386624946176, have=0 ERROR: cannot read chunk root ERROR: cannot open file system Trying to restore partition /dev/sdc1 Hoping to be able to make the missing device accessible again, I tried to use "gdisk" on /dev/sdc, but the output is confusing me: "gdisk /dev/sdc" shows: GPT fdisk (gdisk) version 1.0.9.1 Partition table scan: MBR: not present BSD: not present APM: not present GPT: not present Creating new GPT entries in memory. Command (? for help): q "gdisk /dev/sdb" shows: GPT fdisk (gdisk) version 1.0.9.1 Partition table scan: MBR: MBR only BSD: not present APM: not present GPT: not present *************************************************************** Found invalid GPT and valid MBR; converting MBR to GPT format in memory. THIS OPERATION IS POTENTIALLY DESTRUCTIVE! Exit by typing 'q' if you don't want to convert your MBR partitions to GPT format! *************************************************************** Warning! Secondary partition table overlaps the last partition by 33 blocks! You will need to delete this partition or resize it in another utility. Command (? for help): q Questions What did I do wrong on trying to replace the cache devices? Do you have an idea, how I could be able to restore the data from the cache drives?

https://wiki.unraid.net/UnRAID_6/Configuring_Apple_Time_Machine There is no need to add a remote share to make a Mac do its backup on a unRAID share. It is quite confusing looking for a functionality on the web interface which is part of a plugin named "unassigned devices". Could you please remove the misleading lines in the documentation?

I bought a new graphics card. With the new card assigned to the Lnux Mint VM I can restart the VM without problems.

Booting the Unraid Server and starting the Linux Mint VM works great for the first time. Shuting down the VM and starting it a second time crashes the Unraid Server. The Server is frozen and does not answer on any requests over the keyboard or the unraid web interface. After rebooting the whole Unraid Server the VM is started without troubles, but only one time. After the reboot, the VM feature is disabled and has to be reenabled over the web interface again. The same thing happened also using Debian as guest a while ago on an erlier version of unraid (before 6.7). No troubles with rebooting on Windows 10 as guest OS. If I use VNC instead of mounting my ASUS Radeon HD 5450 graphics card I am able to start Linux Mint as VM several times. Are those troubles caused by the graphics cards? Should I buy me a new graphics card?

I bought and installed a slot bracket with 2x USB 2.0 ports on it connected to the internal USB 2.0 9pin connector on the mainboard [1] After a few BIOS setting changes it booted from the USB 3.0 stick without problems. I had to use legacy boot instead of UEFI. Some CSM settings led to blinking cursors instead of the unRAID boot menu. Now it works and I am happy again with my computer driven by unRAID. Thank you for your help. Once more I had to learn it the hard way: Never touch a running system 🙂 [1] https://www.delock.com/produkte/G_71000/merkmale.html

Thanks for your help so far. I just ordered a new USB 2.0 stick as a replacement for the USB 3.0 which makes trouble. I also ordered an adapter to mount the USB stick to the onboard 2.0 USB ports. I will send an update!

I prepared it the old way: Formatting the whole drive on Windows 10, copied the files to the stick and then made it bootable using the batch script. I also tried the USB creator, which did not help against the boot problems (stick was not recognized as boot device either). It looks like it has got only one partition on it:

Yes, I tried all the ports I got in my system. I also tried to connect the USB stick behind a USB hub. I also tried to disconnect all other USB devices. Nothing helped so far. I also checked that my main bord has got the latest BIOS version.