[Podman](https://podman.io/) is a daemonless alternative to Docker, which is mostly compatible with Docker containers.

# Creating a systemd service file
Podman is easier to run in systemd than Docker due to its daemonless architechture. It comes with a handy generate command which can generate systemd files, here's a [good article going into more detail](https://www.redhat.com/sysadmin/podman-shareable-systemd-services).
```sh
$ podman run -d --name bitwarden -v /bw-data/:/data/:Z -e ROCKET_PORT=8080 -p 8080:8080 bitwardenrs/server:latest
54502f309f3092d32b4c496ef3d099b270b2af7b5464e7cb4887bc16a4d38597
$ podman generate systemd --name bitwarden
# container-foo.service
# autogenerated by Podman 1.6.2
# Tue Nov 19 15:49:15 CET 2019

[Unit]
Description=Podman container-foo.service
Documentation=man:podman-generate-systemd(1)

[Service]
Restart=on-failure
ExecStart=/usr/bin/podman start bitwarden
ExecStop=/usr/bin/podman stop -t 10 bitwarden
KillMode=none
Type=forking
PIDFile=/run/user/1000/overlay-containers/54502f309f3092d32b4c496ef3d099b270b2af7b5464e7cb4887bc16a4d38597/userdata/conmon.pid
```

You can provide a `--files` flag to dedicate a specific file to output the systemd service file to. With this we can enable and start the container as any normal service file.
```sh
$ systemctl --user enable /etc/systemd/system/container-bitwarden.service
$ systemctl --user start container-bitwarden.service
```

## New container every restart
If we want to create a new container every time the service starts we can edit the service file to contain the following:
```sh
[Service]
Restart=on-failure
ExecStartPre=/usr/bin/rm -f /%t/%n-pid /%t/%n-cid
ExecStart=/usr/bin/podman run --conmon-pidfile /%t/%n-pid --env-file=/home/spytec/Bitwarden/bitwarden.conf -d -p 8080:8080 -v /home/spytec/Bitwarden/bw-data:/data/:Z bitwardenrs/server:latest
ExecStop=/usr/bin/podman rm -f --cid-file /%t/%n-cid
KillMode=none
Type=forking
PIDFile=/%t/%n-pid
```
Where `bitwarden.conf` environment file can contain all the container environment values you need
```conf
ROCKET_PORT=8080
```

If you want the container to have a specific name, you might need to add `ExecStartPre=/usr/bin/podman rm -i -f bitwarden` if the process isn't cleaned up correctly.

# Troubleshooting
## Debugging systemd service file
If the host goes down or the container crashes, the systemd service file should automatically stop the existing container and spin it up again. We can find the error through `journalctl --user -u container-bitwarden -t 100`. 

Most of the time the errors we see can be fixed by simply upping the timeout in podman command in the service file.