File and folder permissions issues on Unraid

[BryanWall]

This might be related to #2.

I tried setting up Kopia for the first time today and I am also having a permissions issue on Unraid. I wiped and re-created the container several times before I was able to isolate it to a permissions issue. I don't know if it's entirely a permissions issue, or if there's something else going on also.

What I noticed is that I could access the UI until I create a user (kopia server user add). After I do that and restart the container, the UI no longer works. The log reports no errors, however. I'm not sure if the server isn't even running or if it's just a UI issue, but I suspect the server isn't running in spite of no errors in the log. If I open a console inside the container and copy/paste the CLI_ARGS, the server starts and the UI works.

When I looked at the repository folder I noticed that the permissions on files and folders are somewhat random. I'm not sure what causes it to sometimes create files and folders abc and other times root. Once some of the files are owned by root, things stop working.

drwx------ 1 root root   25 May 26 15:57 _lo
-rw------- 1 abc  abc    30 May 26 15:53 kopia.blobcfg.f
-rw------- 1 root root 1208 May 26 15:57 kopia.maintenance.f
-rw------- 1 abc  abc  1068 May 26 15:53 kopia.repository.f
drwx------ 1 abc  abc    25 May 26 15:53 q00
drwx------ 1 root root   25 May 26 15:57 q7c
drwx------ 1 abc  abc    17 May 26 15:53 s06
drwx------ 1 root root   17 May 26 15:57 s4f
drwx------ 1 abc  abc    40 May 26 15:57 xn0

I changed (chmod) the owner of all of these files and folders to abc and that fixed the issue, but I suspect that if I actually start sending backups to it the permissions issue will return. Running the container as root also fixes it, but I don't want to leave it like that.

This was an instance that I was setting up on a server to be used as an off-site Kopia repository server, to be accessed from another Kopia instance which would be the backup source.

I am not using ZFS, I am using XFS which is the default on Unraid.

[hydazz]

kopia (the service) runs as abc, when you are running kopia server user add you are running it as root, hence those files get created as root, try again fresh but use s6-setuidgid abc kopia server user add...

[BryanWall]

Thank you! That worked. I did some Googling to try to understand how Docker permissions like this work and found this. Would doing what this suggests fix the permissions issue with running commands inside the container?

https://vsupalov.com/docker-shared-permissions/

[hydazz]

I would not, this container does not support --user

https://github.com/imagegenius/docker-kopia/blob/main/root/etc/s6-overlay/s6-rc.d/init-config-kopia/run#L20
Permissions are also fixed on container restart

[BryanWall]

I realize the container doesn't support --user. I thought the article I linked was explaining how to make containers support users correctly, instead of having to brute force the permissions with chown. I'm not sure if there is something about this container that makes that not possible, though.

[hydazz]

it does support users correctly, very similar to whats mentioned under Build the right image in the provided link. there is no 'issue' here, when you run a command as root, and files created as part of that command are going to have the same permissions, which is a issue with every linux distro, s6-setuidgid abc is exactly the same thing as sudo, so you can just run s6-setuidgid abc bash to switch to the abc user, and run whatever kopia commands are needed, and all files created/update will have the correct permissions