Hi all,

 

Having some trouble getting docker to fire up after updating to 6.4 (from 6.1.3).

 

Stopping and starting the docker service doesn't give any errors:

Jan 21 18:26:13 Tower root: starting dockerd ...
Jan 21 18:26:23 Tower emhttpd: shcmd (185): umount /var/lib/docker

Docker Settings: https://pasteboard.co/H41gjvH.png

 

What I've checked:

• Unraid starts up just fine and is able to connect to the web.
• Disks show no read or write errors
• Parity looks good
• Disks have enough space for docker image
• Docker image disk is spun up and I am  able to read from it without issue
• I did not change any docker settings / config during the update process
• I did update community plugins

 

Any help would be appreciated.  Without errors I'm at a bit of a loss.

 

Best,

Rob

Edited January 21, 20188 yr by cablecutter

It's failing to mount for whatever reason.   Easiest to simply disable the service, delete the existing images the recreate it and add back your stuff via apps - previous apps

Thanks.  I was hoping to avoid that if possible, but...seems it might be what I have to do.

For anyone stuck in a similar boat - this was a pretty painless process.  All of the configs were maintained (I thought they'd have to be set up again).  Now I understand why it is the go-to solution.

 

I backed up my docker.img by going to disk1 using CD (where my image is stored) and renaming it with

mv docker.img docker_backup.img

I disabled the docker service in the UI and re-enabled it.  Docker started up without issue.

 

For anyone that's really new - this is what it looked like in the terminal:

XXXXXX@Tower:/mnt# cd disk1
XXXXXX@Tower:/mnt/disk1# ls
CommunityApplicationsAppdataBackup/  Warehouse/  appdata/  docker.img
XXXXXX@Tower:/mnt/disk1# mv docker.img docker_backup.img
XXXXXX@Tower:/mnt/disk1# ls
CommunityApplicationsAppdataBackup/  Warehouse/  appdata/  docker_backup.img

(after restoring my apps)

XXXXXX@Tower:/mnt/disk1# rm docker_backup.img
XXXXXX@Tower:/mnt/disk1# ls
CommunityApplicationsAppdataBackup/  Warehouse/  appdata/  docker.img

 

 

Edited January 22, 20188 yr by cablecutter

The settings you make for each docker is stored on the flash drive and that's how CA is able to reinstall them with the same settings.

 

Not sure there is really any point to backing up the docker.img. Getting it to use that backup would be kind of complicated and since it was corrupt anyway you don't really want it.

 

More importantly, you should try to find out why it got corrupted in the first place. The most likely cause is it filled up. docker.img is a virtual disk, and you specify its size on the same page where you enable the docker service.

 

You can get an idea of how full docker.img is by looking on the dashboard near the lower left where it shows the percent full of flash log docker. See the Docker FAQ for more on how to deal with docker.img filling up.

 

 

At some point it was required to rebuild the docker image when a newer - and non-compatible - version of docker was introduced. To be honest I don't remember if this is required when upgrading from 6.1.3 to 6.4.0.

 

The docker image disk format incompatibility is due to the obsolete version of docker used in 6.1.3 -> so any future version of unRAID will require the docker image rebuild. You should only need to do this once though.