Moving docker installation with new docker-compose

m4tt0 · Jun 24th 2023

I've been running docker for some time on my OMV6 system. I've also upgrade to the new docker-compose system, without major problems.

Today, I had to exchange an SSD drive, which contained my AppData, docker and compose folders.

Obviously, I had to remove all references from the old SSD filesystem in order to swap the drive.

It eventually ran well, but I struggled to properly transition the docker environment itself:

- I first stopped and removed all containers (using the "down" button on the "Files" section)

- I then tried to find a place to stop the docker environment, but could not find it

- I eventually decided to uninstall the docker-compose plugin, as it obviously contained references to the SSD filesystem as well.

- I did not disable the docker repo under OMV-extras, because I thought that it just adds the apt repo to the system. Maybe that was wrong?

- In any case, after this I was able to unount the old SSD, insert the new one and reestablish the AppData and compose folders, shared folders, etc.

- I then "apt-cleaned" the docker repo and reinstalled the docker-compose plugin

- In the docker-compose settings, I inserted the "new" shared folders, which I created on the new SSD (of course with the "old" content").

- I saved the changes and clicked "reinstall docker", but the installation fails. It still does when I do it. Error message attached.

- I can fix the installation by running "omv-upgrade" via CLI. It says that docker-ce is not fully installed. Afterwards everything runs fine.

Any idea what goes wrong here? Or is it a problem with the new docker integration?

ryecoaaron · Jun 24th 2023

Quote from m4tt0

I then tried to find a place to stop the docker environment, but could not find it

You don't need to. The only thing you need to keep is the persistent volumes. The compose files are stored in the omv database and will be rewritten to the filesystem when you change the shared folder.

Quote from m4tt0

I did not disable the docker repo under OMV-extras, because I thought that it just adds the apt repo to the system. Maybe that was wrong?

Nope. No need to.

Quote from m4tt0

- I eventually decided to uninstall the docker-compose plugin, as it obviously contained references to the SSD filesystem as well.

You could've just created another temporary shared folder on a different drive and use that in the plugin. Uninstalling the plugin means you could lose the database entries. You should never have to uninstall the plugin.

Quote from m4tt0

I saved the changes and clicked "reinstall docker", but the installation fails. It still does when I do it. Error message attached.

Did you copy the data in the "docker" directory to the new ssd? You shouldn't if you did. What is the output of: sudo journalctl -u docker

m4tt0 · Jun 24th 2023

Thanks for looking into it and your explanations!

As to your question: No, I did not copy the "docker" directory to the new ssd. I've read the omv-extra Wiki entry on docker (which is actually excellent!) and understood that it will be rebuild with a new docker installation.

I'm attaching the output of the journalctl -u docker command. It's a txt file, but I had to zip it, not to exceed the file size limit.

ryecoaaron · Jun 24th 2023

First, I wouldn't use a mergerfs pool for the docker path in the Docker section of the Settings tab.

Second, the path you specified doesn't seem to exist.

failed to start daemon: error while opening volume store metadata database (/srv/mergerfs/data/docker/volumes/metadata.db): no such device

m4tt0 · Jun 24th 2023

OK, that path is wrong. I used the /srv/mergerfs/data/ path to store the old SSD content, i.e. the AppData, docker and compose directories. I then changed the docker path in the docker-compose settings to the mergerfs path, to get rid of the the old SSD reference. That must have been before I uninstalled the docker-compose plugin. After reinstalling it, I set a different path, i.e. /srv/dev-disk-by-uuid-5c8e8fc1-94ee-431e-b45e-7939d6339072/docker, which references the new SSD. That is also the path that shows in the docker-compose Settings page. I've just checked it again.

And yes, I have deleted the directories on my mergerfs after copying them back to my new SSD, so I'm not surprised they are not found anymore. I wonder why the temporary path persists in the configuration...

chente · Jun 24th 2023

The error has been to use a mergerfs pool to redirect the folders. You could have created a folder on one of the pool drives and used that path instead of the pool path.

Do you already have it working? What do you mean by "temporary path persist in the configuration"? What is that temporary path?

m4tt0 · Jun 24th 2023

I have it working, but only by manually running "omv-upgrade" as indicated in the original post.

If I try to restinall docker via the docker-compose settings menu, I still get the same errors I initially reported. Whenever I do that, I have to run "omv-upgrade". So something is still wrong.

With "temporary path" I referred to the directory I created on my mergerfs to temporarily store my AppData and compose folders. This was only done to swap the SSD. With "persisting" I referred to ryecoaaron 's observation that this path still appears in the output of journlctl. I therefore assumed that something is wrong with the configuration.

chente · Jun 24th 2023

Have you already copied the folders to the new SSD? And if so, have you already defined the "compose" folder in the plugin GUI in the Shared Folder field?

m4tt0 · Jun 24th 2023

Yes, all done. And they all correctly point to the new SSD. All my containers are up and running as well after fixing the installation with "omv-upgrade".

chente · Jun 24th 2023

I would try to create a new docker installation folder on the new SSD drive. If you already have one called docker you can create another dockertest. Then change the docker path to that folder and click on the Save button (don't forget this button) and the Reinstall docker button. Just to see if that cleans up the install.

If this works I would clean up the original docker folder to get back to that location.

m4tt0 · Jun 24th 2023

Didn't help. I created the new docker directory using "mkdir". Changed the shared folder accordingly (see screenshot). Same errors as in my original post, but attached as txt-file again...

chente · Jun 24th 2023

Based on what I'm seeing here, what you've done is change the path of the shared folder. What I said was to create a new docker_test folder. I'm not sure if what you've done is effective since you haven't actually changed the GUI path of the plugin.

chente · Jun 24th 2023

What I'm trying with this is to have the plugin reinstall docker in a completely different folder than the old one.

m4tt0 · Jun 24th 2023

I have. Please look further right. There you see the "dockertest" folder I created following your recommendation. It was empty before I reinstalled docker. Now it contains a folder structure, which was not there before...

chente · Jun 24th 2023

Yeah. But the path in the GUI is still the same as before. I think that changing that route could bring other changes.

Look at the error you got. What route is this?

Code

----------
          ID: docker_install_packages
    Function: pkg.installed
      Result: False
     Comment: Problem encountered installing package(s). Additional info follows:

              errors:
                  - Running scope as unit: run-ra7161a77581141018da01a25ea50d7bd.scope
                    E: Sub-process /usr/bin/dpkg returned an error code (1)
     Started: 20:36:37.163522
    Duration: 10794.522 ms
     Changes:
----------

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chente · Jun 24th 2023

I don't know if it will work, but you have nothing to lose by trying. If it doesn't work, well, you know, ryecoaaron will have to squeeze his neurons.

m4tt0 · Jun 24th 2023

Yes, I've seen the error, but have no idea what the ra71... refers to.

I've rm -rf'ed the dockertest folder again. Recreated it. I removed the old "docker" shared folder completely. I've created a new shared folder "dockertest" and linked it to the empty "dockertest" directory. I then updated the docker path in docker-compose Settings (it is an absolute path, not a shared folder though). Saved the changes. Reinstalled docker. Same error...

Sorry, if I still misunderstand what you try me to do...

chente · Jun 24th 2023

ok, now you have done what I was trying to tell you, but unfortunately it seems that it has not served for anything. Thanks.

A question that just popped into my mind. When you changed the folders to your mergerfs pool to change the SSD disk, did you do it like this too? Did you only change the path of the shared folders?

m4tt0 · Jun 24th 2023

I'm pretty sure that I only changed the absolute path in the docker-compose Settings section, but I did not change the shared folder. In fact, I deleted the old docker shared folder, as my objective was to dereference my old SSD, because I wanted to swap it.

I saw no requirement to create another shared folder for docker, as only the absolute path is referenced in the docker-compose settings menu. This is obviously different for the compose entry in the same menu, where the shared folder is used and not the absolute path. It's a bit confusing why you want one or the other, but I didn't question it...

chente · Jun 24th 2023

Quote from m4tt0

In fact, I deleted the old docker shared folder, as my objective was to dereference my old SSD, because I wanted to swap it.

Sure, logical, you needed to delete it.

Quote from m4tt0

It's a bit confusing why you want one or the other, but I didn't question it...

If you don't mind, can you post a screenshot of the GUI under Services>Compose>Settings ? It wouldn't be the first time I've seen errors on that screen, despite its simplicity.

Moving docker installation with new docker-compose

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