homelab/templates/podman/foobar.md

# Podman foobar

- [Podman foobar](#podman-foobar)
  - [Setup foobar Project](#setup-foobar-project)
  - [Install foobar](#install-foobar)
    - [Create the foobar user](#create-the-foobar-user)
    - [Write the foobar compose spec](#write-the-foobar-compose-spec)
      - [A Note on Volumes](#a-note-on-volumes)
    - [Convert foobar compose spec to quadlets](#convert-foobar-compose-spec-to-quadlets)
    - [Create any container-mounted directories](#create-any-container-mounted-directories)
    - [Start and enable your systemd quadlet](#start-and-enable-your-systemd-quadlet)
    - [Expose foobar](#expose-foobar)
      - [firewalld](#firewalld)
  - [Backup foobar](#backup-foobar)
  - [Upgrade foobar](#upgrade-foobar)
    - [Upgrade Quadlets](#upgrade-quadlets)
  - [Uninstall](#uninstall)
  - [Notes](#notes)
    - [SELinux](#selinux)

## Setup foobar Project

- [ ] Copy and rename this folder to active/podman_foobar
- [ ] Find and replace foobar with the name of the service.
- [ ] Create the rootless user to run the podman containers
- [ ] Write the compose.yaml spec for your service
- [ ] Convert the compose.yaml spec to a quadlet
- [ ] Install the quadlet on the podman server
- [ ] Expose the quadlet service
- [ ] Install a backup service and timer

## Install foobar

### Create the foobar user

```bash
# SSH into your podman server as root
useradd foobar
loginctl enable-linger $(id -u foobar)
systemctl --user --machine=foobar@.host enable podman-restart
systemctl --user --machine=foobar@.host enable --now podman.socket
mkdir -p /home/foobar/.config/containers/systemd
```

### Write the foobar compose spec

Edit the compose.yaml at active/podman_foobar/compose/compose.yaml

#### A Note on Volumes

Named volumes are stored at `/home/foobar/.local/share/containers/storage/volumes/`.

### Convert foobar compose spec to quadlets

Run the following to convert a compose.yaml into the various `.container` files for systemd:

```bash
# Generate the systemd service
podman run \
--security-opt label=disable \
--rm \
-v $(pwd)/active/podman_foobar/:/compose \
-v $(pwd)/active/podman_foobar/quadlets:/quadlets \
quay.io/k9withabone/podlet \
-f /quadlets \
-i \
--overwrite \
compose /compose/compose.yaml

# Copy the files to the server
export PODMAN_SERVER=
scp -r active/podman_foobar/quadlets/. $PODMAN_SERVER:/home/foobar/.config/containers/systemd/
ssh $PODMAN_SERVER chown -R foobar:foobar /home/foobar/.config/containers/systemd/
```

### Create any container-mounted directories

SSH into your podman server as root:

```bash
machinectl shell foobar@
podman unshare
mkdir some_volume
# Chown to the namespaced user with UID 1000
# This will be some really obscure UID outside the namespace
# This will also solve most permission denied errors
chown -R 1000:1000 some_volume
```

### Start and enable your systemd quadlet

SSH into your podman server as root:

```bash
machinectl shell foobar@
systemctl --user daemon-reload
systemctl --user restart foobar
# Enable auto-update service which will pull new container images automatically every day
systemctl --user enable --now podman-auto-update.timer
```

### Expose foobar

1. If you need a domain, follow the [DDNS instructions](/active/podman_ddns/ddns.md#install-a-new-ddns-service)
2. For a web service, follow the [Caddy instructions](/active/podman_caddy/caddy.md#adding-a-new-caddy-record)
3. Finally, follow your OS's guide for opening ports via its firewall service.

#### firewalld

```bash
# command to get current active zone and default zone
firewall-cmd --get-active-zones
firewall-cmd --get-default-zone

# command to open 443 on tcp
firewall-cmd --permanent --zone=<zone> --add-port=443/tcp

# command to open 80 and 443 on tcp and udp
firewall-cmd --permanent --zone=<zone> --add-port={80,443}/{tcp,udp}

# command to list available services and then open http and https
firewall-cmd --get-services
firewall-cmd --permanent --zone=<zone> --add-service={http,https}
```

## Backup foobar

Follow the [Borg Backup instructions](/active/systemd_borg/borg.md#set-up-a-client-for-backup)

## Upgrade foobar

### Upgrade Quadlets

Upgrades should be a repeat of [writing the compose spec](#convert-foobar-compose-spec-to-quadlets) and [installing the quadlets](#start-and-enable-your-systemd-quadlet)

```bash
export PODMAN_SERVER=
scp -r quadlets/. $PODMAN_SERVER$:/home/foobar/.config/containers/systemd/
ssh foobar systemctl --user daemon-reload
ssh foobar systemctl --user restart foobar
```

## Uninstall

```bash
# Stop the user's services
systemctl --user disable podman-restart
podman container stop --all
systemctl --user disable --now podman.socket
systemctl --user disable --now podman-auto-update.timer

# Delete the user (this won't delete their home directory)
# userdel might spit out an error like:
# userdel: user foobar is currently used by process 591255
# kill those processes and try again
userdel foobar
```

## Notes

### SELinux

<https://blog.christophersmart.com/2021/01/31/podman-volumes-and-selinux/>

:z allows a container to share a mounted volume with all other containers.

:Z allows a container to reserve a mounted volume and prevents any other container from accessing.