Since upgrading to 7.1.4 from 7.1.2 I've been getting random occurrences of the following error "Docker Service failed to start".

Steps I've tried to resolve this

1. After error occurred, go to Settings, Docker, Enable Docker, off, apply, than turning back on, apply. Error remained the same, Docker service was not restarted.

2. On reddit, https://www.reddit.com/r/unRAID/comments/uhdhuz/docker_service_failed_to_start/ it was suggested to increase the Docker vDisk size. I tried this with no effect on the error.

3. from terminal, call "/etc/rc.d/rc.docker restart" . This did get docker running again but several of my containers which use static assigned IPs would not start

4. Reboot server, this always gets everything back working but for an unknown amount of time.

Prior to 7.1.4 I've not seen this failure mode. diagnostics attached

Thanks for any help to resolve this issue.

Error shown on docker tab.

to

tower-diagnostics-20250707-0751.zip

Edited July 8, 2025Jul 8 by mwasserman

Appears you are having issues with your cache pool... Might want to check there

Jun 24 08:14:18 Tower kernel: BTRFS info (device nvme0n1p1): bdev /dev/nvme1n1p1 errs: wr 26624243, rd 19056641, flush 145986, corrupt 216843, gen 0

Looks like read/write errors and corruption.

Edited July 8, 2025Jul 8 by MowMdown

One of the pool devices dropped offline in the past, scrub the pool and post the results from the GUI.

Thanks for the tips, yes. I've been having random drop outs of my Cache nvme drives. I'm running 2x btrfs as a mirrord set.

I have found that every time I have a nvme drive drop out, it comes right back after a system reboot. I did run scrub (sorry I don't have a screen shot). Scrub found many correctable errors. On a 2nd pass of scrub no errors were detected.

Others seem to think there may be an issue with btrfs and unraid. https://www.reddit.com/r/unRAID/comments/18wkga3/frequent_crashing_resolved_by_cache_migration/ .

My plan is to

1. Pull all the data off Cache

2. Format as ZFS

3. bring the data back to Cache

4. remove and rebuild the docker.img

I'll report back with any results.

Devices dropping offline is not a BTRFS issue, likely the same will happen with zfs, recomend better pool monitoring with either: https://forums.unraid.net/topic/46802-faq-for-unraid-v6/page/2/#findComment-700582

Wanted to report back with some updates.

Hard to know if this was related but had been using Intel Graphics SR-IOV to split the GPU of my i7-14700K for use with Plex (Container) + VM (games). Unknown if this was the root cause of any of the drive dropouts but I disabled that plugin for now and moved to a dedicated pass though GPU.

Moved catch from BTRFS to ZFS. Hoping that if I do get a drive dropout, I won't be dealing with some of the corruption problems I had with BTRFS during a drive dropout.

4 days running this setup so far with zero issues

Update: 24 days, no issues after the above changes. I'm officially a ZFS fan

Edited August 2, 2025Aug 2 by mwasserman
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