ServeUnix group argument always 'docker'?

[ahmetb]

It appears like when we create plugin sockets the group must be either root or docker. Root worked fine for me for a while until I tried my plugin on CoreOS (it basically said root group not found, but it was there). So I switched to docker group, which I believe the right thing to do.(?)

Is there a use case where this group argument might be something other than "docker" value?

[CWSpear]

@ahmetalpbalkan why did you close this? What did you discovered? I'm running into the same issue where root doesn't work on CoreOS.

[ahmetb]

I closed due to inactivity. Reopening in case you want to follow up.

[CWSpear]

Yeah, indeed, I'm seeing issues with CoreOS giving an error root group not found, but it works if you use docker. docker seems to work elsewhere. I did a search on GitHub and the vast majority seem to pass root to handler.ServeUnix.

[dave-tucker]

I'm pretty sure the gid needs to be the same as is used for docker. As for what that gid is, it will vary depending on how Docker is packaged. The most sensible option for plugin authors is to allow the gid to be user specified, but I think in most cases root seems to do the trick.