Entrypoint and volumes improvement

[rikislaw]

changes:

1. SELinux label is not added by default to all volumes/mounts when we specify usage of SELinux label in main Nomad config for Podman driver. This setting goes only to standard Nomad mounts. For volumes defined in job definition, we need to provide z label for each volume, where we want to use it. With previous approach I was not able to mount share, that didn't require providing z label at all. I had this issue on RHEL7/8 with enabled selinux and for NFS mounts. NFS mounts were not working (permission denied) when mounted with z label.
2. Entrypoint works exactly the same as for Docker driver. I changed it mainly because with current approach I was not able to disable entrypoint provided in the image and use only CMD.

[hashicorp-cla]

All committers have signed the CLA.

[lgfa29]

Hi @rikislaw 👋

Thank you for the PR!

Matching the entrypoint behaviour to the Docker task driver makes sense to me. But this would be breaking change since it modifies the type of an existing driver configuration, so we'll need to be a bit more careful merging and releasing this change.

As for the SELinux label change, this was suggested before in #66 but there were some concerns about the impact on CSI volumes.

Would you mind splitting this PR into two so we can manage the changes separately?

Thanks!

[rikislaw]

Hi @lgfa29 , thanks for comments, I created two new PRs:
#208
#209

Regarding Entrypoint PR, I will create also alternative solution in another PR. This one will be not breaking.

I'm closing this PR.