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Quellen/IT/Creating User’s Services With systemd.md

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+---
+title: Creating User’s Services With systemd | Baeldung on Linux
+source: https://www.baeldung.com/linux/systemd-create-user-services
+tags:
+  - IT/Administration
+  - IT/OS/Linux
+---
+
+ 
+
+## 1\. Overview
+
+Most Linux distributions use [*systemd*](https://www.baeldung.com/linux/create-remove-systemd-services) as a contemporary service manager. Usually, we need to become *root* to control the services. **However, we can also allow ordinary users to handle services on their own.** This method is often called rootless.
+
+In this tutorial, we’ll learn to install, manage and control services on a per-user basis.
+
+## 2\. Creating and Adding a Sample Service
+
+First, let’s write a simple Bash script *user_service* for the service:
+
+```bash
+#!/bin/bash
+
+while true
+do
+    now=$(date)
+    me=$(whoami)
+    echo "User $me at $now"
+    sleep 10
+done
+```
+
+So, the script prints the date and user name. Then, we need to copy the script to the */usr/local/bin* directory and make sure that the user has executable permission on it.
+
+Next, let’s prepare the [service’s unit file](https://man7.org/linux/man-pages/man5/systemd.unit.5.html) *user_service.service*:
+
+```properties
+[Unit]
+Description=Script Daemon For Test User Services
+
+[Service]
+Type=simple
+#User=
+#Group=
+ExecStart=/usr/local/bin/user_service
+Restart=on-failure
+StandardOutput=file:%h/log_file
+
+[Install]
+WantedBy=default.target 
+```
+
+Since the entries *User* and *Group* are meaningless for user service, we’ve commented them out. Next, we redirect the script’s output to *log_file* with the *StandardOutput* entry. It’s worth noting that the *%h* modifier stands for the user’s home directory.
+
+**Now, with the [sudo](https://www.baeldung.com/linux/sudo-command) privilege let’s copy the unit file to the */etc/systemd/user* directory.** In this way, *systemd* regards the service as the user’s one. Moreover, the service is available for all users.
+
+## 3\. The *user* Option
+
+We can manage services as regular users with the help of the *user* option of [*systemctl*](https://www.baeldung.com/linux/differences-systemctl-service#systemctlcommand). Thus, services can be enabled/disabled, started/stopped, and so on without the sudo privilege.
+
+So, let’s install the service:
+
+```bash
+systemctl --user daemon-reload
+```
+
+Afterwards, let’s start it:
+
+```bash
+systemctl --user start user_service.service
+```
+
+Next, let’s check its status:
+
+```bash
+systemctl --user status user_service.service
+● user_service.service - Script Daemon For Test User Services
+     Loaded: loaded (/etc/xdg/systemd/user/user_service.service; disabled; vendor preset: enable>
+     Active: active (running) since Thu 2023-01-12 19:23:14 CET; 28s ago
+   Main PID: 4935 (user_service)
+      Tasks: 2 (limit: 18982)
+     Memory: 580.0K
+        CPU: 16ms
+     CGroup: /user.slice/user-1000.slice/user@1000.service/app.slice/user_service.service
+             ├─4935 /bin/bash /usr/local/bin/user_service
+             └─4972 sleep 10
+
+sty 12 19:23:14 ubuntu systemd[1511]: Started Script Daemon For Test User Services.
+```
+
+Again, we should note that we’ve done that all without the *sudo* command.
+
+## 4\. Enabling, Disabling, and the Service’s Lifetime[](#enabling-disabling-and-the-services-lifetime)
+
+Now let’s enable or disable the service with *systemctl*:
+
+```bash
+systemctl --user enable user_service.service
+Created symlink /home/joe/.config/systemd/user/default.target.wants/user_service.service → /etc/xdg/systemd/user/user_service.service.
+```
+
+**Thus, once enabled, the service starts automatically after our login.** Then, it’ll be running as long as we have some open sessions. In other words, the service instance is bound to the user, not to the session.
+
+Finally, let’s disable it:
+
+```bash
+systemctl --user disable user_service.service
+```
+
+## 5\. Toggling Services of All Users[](#toggling-services-of-all-users)
+
+With the root privilege, we can enable or disable the service for all users with the *global* option of *systemctl*:
+
+```bash
+sudo systemctl --global enable user_service.service
+Created symlink /etc/systemd/user/default.target.wants/user_service.service → /etc/systemd/user/user_service.service.
+```
+
+**Consequently, all users obtain their own running instance of the service immediately after login.**
+
+## 6\. Extending Service’s Life
+
+Let’s assume that we intend our service to perform long-running tasks, e.g., calculation. So, we should extend its life beyond the end of the last session. **In that case, we use [*loginctl*](https://man7.org/linux/man-pages/man1/loginctl.1.html) with the *enable-linger* command:**
+
+```bash
+$ loginctl enable-linger
+```
+
+Now, our services start right after the system boot and run till the shutdown. We should keep in mind that this applies to all our *systemd* services. Finally, we can turn it off with *disable-linger*.
+
+## 7\. Inspecting Service’s Log
+
+Now let’s check the service’s log with the [*journalctl*](https://www.baeldung.com/linux/journalctl-check-logs) command. Once again, we’ll use the *user* option:
+
+```bash
+$ journalctl --user -u user_service
+# ...
+Jan 12 19:50:20 ubuntu systemd[1511]: Stopped Script Daemon For Test User Services.
+Jan 12 19:50:24 ubuntu systemd[1511]: Started Script Daemon For Test User Services.
+```
+
+## 8\. Conclusion
+
+In this article, we looked at user services managed by *systemd*.
+
+First, we created a simple service and added it to the *systemd* using the administrator privilege. **Then, we managed the service as a non-sudoer thanks to the *user* option of *systemctl*.**
+
+Subsequently, we took a look at the lifetime of service and learned how to start the service without login. Finally, we examined the service’s log.