> ## Documentation Index
> Fetch the complete documentation index at: https://docs.opus-host.de/llms.txt
> Use this file to discover all available pages before exploring further.

# Run Apps as systemd Services on Your Opus Host VPS

> Keep your apps running after logout and reboot. Create, enable, and manage systemd services on your Opus Host VPS with a copy-paste template.

When you close your SSH session, anything you started in that shell dies with it. systemd fixes this: it runs your app as a background service, restarts it if it crashes, and starts it automatically when the server boots. If you want a bot, web app, or game server to just stay up, this is how you do it.

## Anatomy of a service file

Systemd service files live in `/etc/systemd/system/` and end in `.service`. Here is a template you can adapt for any long-running app:

```ini theme={null}
[Unit]
Description=My App
After=network.target

[Service]
Type=simple
User=alice
WorkingDirectory=/home/alice/myapp
ExecStart=/usr/bin/node /home/alice/myapp/index.js
Restart=on-failure
RestartSec=5

[Install]
WantedBy=multi-user.target
```

Key fields:

* **User** — which user the process runs as. Avoid `root` when possible.
* **WorkingDirectory** — the app's working directory, as if you had `cd`'d there.
* **ExecStart** — the command to run. Use absolute paths.
* **Restart=on-failure** — restart if the process exits with an error.

## Create and enable a service

<Steps>
  <Step title="Write the service file">
    ```bash theme={null}
    sudo nano /etc/systemd/system/myapp.service
    ```

    Paste the template above and adjust the fields for your app.
  </Step>

  <Step title="Reload systemd so it picks up the new file">
    ```bash theme={null}
    sudo systemctl daemon-reload
    ```
  </Step>

  <Step title="Start the service">
    ```bash theme={null}
    sudo systemctl start myapp
    ```
  </Step>

  <Step title="Enable it on boot">
    ```bash theme={null}
    sudo systemctl enable myapp
    ```
  </Step>
</Steps>

## Manage a service

```bash theme={null}
sudo systemctl status myapp     # show current state
sudo systemctl stop myapp       # stop
sudo systemctl restart myapp    # restart
sudo systemctl disable myapp    # stop starting on boot
```

## View logs

systemd captures your app's stdout and stderr automatically — no log file setup required.

```bash theme={null}
# Follow logs in real time
sudo journalctl -u myapp -f

# Show the last 100 lines
sudo journalctl -u myapp -n 100

# Only logs since the last boot
sudo journalctl -u myapp -b
```

<Tip>
  If your service fails to start, `sudo systemctl status myapp` usually tells you why in the last few lines of output. When it does not, `journalctl -u myapp -n 50` will.
</Tip>