It appears my main cache drive is failing. This is a HDD where the other two are SSD so I had planned on removing it anyway. The instructions for removing a drive from a cache pool are numerous and each a bit different. But my goal was to do something like this:

 

[*]Balance Cache

[*]Backup Cache Drive

[*]Stop the array using the webUI

[*]Remove drive to the cache pool

[*]Disconnect power/sata from removed drive

[*]Start the array

[*]Wait for the updated pool to rebalance which will also delete from the pool

 

The initial balance process seems to be hung(?) at: 21 out of about 57 chunks balanced (22 considered),  63% left

 

 

Any insight into how to handle this? Diagnostics attached.

 

[edit] file too big, apparently... here is a download link: https://1drv.ms/u/s!AlrZB2zl8cavgcso3gs6TsVTgw7dvQ

Adding some detail - the balance seems to be never ending. I see:

 

Jul 27 11:30:58 Juggernaut kernel: BTRFS info (device sdc1): found 1 extents

Jul 27 11:30:59 Juggernaut kernel: BTRFS info (device sdc1): found 1 extents

Jul 27 11:30:59 Juggernaut kernel: BTRFS info (device sdc1): found 1 extents

Jul 27 11:31:00 Juggernaut kernel: BTRFS info (device sdc1): found 1 extents

Jul 27 11:31:00 Juggernaut kernel: BTRFS info (device sdc1): found 1 extents

Jul 27 11:31:00 Juggernaut kernel: BTRFS info (device sdc1): found 1 extents

 

 

goes on and on - several times per second.

 

Screenshot with drive labels attached.

 

 

If one of the cache disks is failing you may not be able to complete the balance, though SMART for the wd looks OK, I can't really tell if all those BTRFS errors are from a bad disk or corrupted filesystem.

... I can't really tell if all those BTRFS errors are from a bad disk or corrupted filesystem.

 

As for how to approach correcting it, any suggestions? Wipe the cache drives, reformat, and start over?

If it's already back up probably best to create a new pool with the SSDs only, disconnect the other disk and format the SSDs to a different fs (like reiser) before adding them to the new pool, then format to BTRFS again.