I noticed that docker wasn't running on my unraid server. Checked the logs and noticed a number of errors on startup. I am hoping that someone can help me trouble shoot this. Attached are the logs. I am particularly interested in this error.

Dec 14 16:46:03 HomeServer kernel: loop: Write error at byte offset 38899712, length 4096.
Dec 14 16:46:03 HomeServer kernel: blk_update_request: I/O error, dev loop2, sector 75968 op 0x1:(WRITE) flags 0x1800 phys_seg 4 prio class 0
Dec 14 16:46:03 HomeServer kernel: BTRFS error (device loop2): bdev /dev/loop2 errs: wr 1, rd 0, flush 0, corrupt 0, gen 0

 

This unraid 6.9.2 on an older i7 processor with 4 drives in an array and a SSD cache drive.

homeserver-syslog-20211215-1610.zip

By itself, that error means the docker.img needs to be deleted and recreated  https://forums.unraid.net/topic/57181-docker-faq/#comment-564309

 

But you have some other issues the Fix Common Problems is complaining about.  Can you post your diagnostics

Diagnostics attached, thanks for the quick reply.

homeserver-diagnostics-20211215-0927.zip

Looks ok.  The disks being unable to be written to is correct (1-3 are all 100% full).  Follow my original link

That seems to have fixed it. Reinstalling dockers now.

 

What causes this and is there a way to prevent it?

Easiest way is that due to a misconfiguration the image fills up to 100%  Reinstalling those is super easy via Apps - Previous Apps

I did get a warning about the image being full. I still need to track down what that was, maybe plex.

4 hours ago, potts.mike said:

I did get a warning about the image being full. I still need to track down what that was, maybe plex.

The usual reason for filling docker.img is an application writing to a path that doesn't correspond to a container path in the mappings, case-sensitive. Check the settings within each of your applications and make sure they only specify paths that are mapped.