Linux GUI and CLI mode

Short guide to switch between GUI and CLI (text) Linux interface

System/linux-gui-cli.adoc

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+= GUI-or-CLI - Interfacce GUI e CLI per Linux
+Sottotitolo documento
+:authors: Celestino Amoroso
+:docinfo: shared
+:encoding: utf-8
+:toc: right
+:toclevels: 4
+:toc-title: Indice Generale
+:icons: font
+:icon-set: fi
+:numbered:
+:table-caption: Tabella
+:figure-caption: Diagramma
+:docinfo1:
+:sectlinks:
+:sectanchors:
+:source-highlighter: rouge
+// :rouge-style: ThankfulEyes
+:rouge-style: gruvbox
+// :rouge-style: colorful
+//:rouge-style: monokay
+
+toc::[]
+
+## Switch between GUI and CLI
+
+To switch to text mode (also known as command-line interface or CLI) in systemd-based systems, you can use systemctl `set-default multi-user.target` to permanently change the default boot target. Alternatively, you can temporarily switch to text mode using `systemctl isolate multi-user.target`.
+
+Here's a breakdown of how to switch to text mode:
+
+### 1. Checking the Current Default Target*
+First, it's helpful to know what your current default target is. You can check this with: 
+
+  systemctl get-default
+
+This command will display the current default target, which is likely `graphical.target` if you're currently in a graphical environment.
+
+
+### 2. Permanently Switching to Text Mode (Multi-User Target)
+To make text mode the default target on boot, use the following command:
+
+  sudo systemctl set-default multi-user.target
+
+After running this command, you will need to reboot your system for the change to take effect:
+
+  sudo systemctl reboot
+
+Now, when your system starts, it will boot directly into text mode. 
+
+
+###3. Temporarily Switching to Text Mode (Using isolate)
+If you want to switch to text mode without changing the default, you can use the isolate command:
+
+  sudo systemctl isolate multi-user.target
+
+This command will immediately switch your system to text mode without requiring a reboot. However, the next time you boot, it will revert to the default target (which you can set using set-default as described above).
+
+
+### 4. Switching Back to Graphical Mode
+To switch back to graphical mode, you can use the following command (if you previously used set-default):
+
+  sudo systemctl set-default graphical.target
+
+And then reboot:
+
+  sudo systemctl reboot
+
+Or, if you used isolate, you can switch back with:
+
+  sudo systemctl isolate graphical.target
+
+## Important Notes
+
+### multi-user.target
+This target represents a system with networking enabled but without a graphical interface (X server or Wayland).
+
+### graphical.target
+This target represents a system with a graphical interface.
+
+### Reboot
+When changing the default target, a reboot is necessary for the change to be applied.
+
+### Temporary changes
+Using isolate provides a temporary change that is not persistent across reboots. 
+
+### Closing Applications
+Switching to text mode will terminate any running graphical applications. Make sure to save your work before switching. 
+
+
+'''
+*Celestino Amoroso* +
+*celestino . amoroso @ gmail . com*
+
+image::https://gravatar.com/avatar/88d204d546890e5d89073fb1cec29fe9.png?size=48[]
+