## Powering On the Computer

The operating system installed on the storage device starts automatically after turning on the PC and executing the BIOS programs. A special program — the GRUB bootloader — is used to load the OS.

Before the operating system boots, you have the option to enter the “Boot Menu” to select a boot mode, change the operating system to load, or configure system settings.

To access the “Boot Menu”, you must press the `ESC` key within 3 seconds after the system starts. If the `ESC` key is not pressed in time, the system will automatically boot into the default mode.

- Boot Menu Enter the boot menu, configure bootloader settings, including boot modes and other OS options

> By default, the system boots in full persistence mode.

> Authentication credentials for accessing protected GRUB menu entries (by default):
> Username: superadmin
> Password: ublinux-grub

During system boot, a splash screen (Plymouth) is displayed:

To view the boot log, press the `ESC` key during startup:

## User Authentication

After the OS has finished booting, a welcome screen appears prompting the user to authenticate:

The top panel includes: - - hostname; - - day of the week and time; - - keyboard layout; the enabled Scroll Lock indicator on the keyboard also shows that the Russian keyboard layout is active; - us_ru - English (US); - ru - Russian. - - desktop environment selection; - - accessibility options: large text (F1), high contrast (F2), on-screen keyboard (F3);

- - suspend/sleep, reboot, and shutdown.

Below is the icon of the boot mode:

If the root password and the password of the user with UID 1000 are the same and set by default to “ublinux”, a password hint will be displayed on the login screen:

> “ublinux” is the default password for all user accounts. After changing the password, the authentication background will be changed to one without the password hint.

Once valid authentication credentials have been entered, UBLinux will load the user’s desktop.

> If incorrect authentication credentials are entered more than 3 times, the account will be locked. To immediately unlock the account, open a console with the key combination `Ctrl` + `Alt` + `F2`, log in as an administrator, and run the following command: `faillock --user user-1 --reset` Where: user-1 is the name of the user to unlock. To return from the console to the graphical session, press: `Ctrl` + `Alt` + `F7`

## Desktop

The desktop contains standard shortcuts: Trash, File System, and Home Directory.

In the background of the desktop, there is a floppy disk icon by default. This icon indicates the mode in which the system was booted. There are four available boot modes:

Full persistence on HDD. Data is saved normally to the storage device; Sandbox in RAM with user profile saved to HDD. Only changes in the /home directory are saved; Full sandbox in RAM. Data is not saved; Persistence to HDD module. Data is saved as a changes module to the storage device.

> More about boot modes: Boot Modes
> More about changing boot mode: Boot Menu Access

> You can also check the current boot mode using the utility “System Boot”.

On the bottom panel, to the left, there is an applications menu through which you can find the desired program, access settings, lock the session, or open the power menu for actions like shutdown, reboot, switch user, etc.
The menu includes a “Recent” tab displaying recently launched applications for quick access.

This menu can also be opened using the `win` key.

> The search bar allows you to find programs not only by their name but also by their description.

On the right side of the panel, there is a system tray, which contains:
- Notes;
- Keyboard layout;
- Clipboard;
- Network connection icon;
- Update module;
- Status tray module (application indicators);
- Volume icon;
- Date and time;
- Screenshot tool.

## Home Directory

By default, programs save files to the user’s home directory.
All user home directories are located in `/home/`.
The name of the user’s directory matches the user’s login in the system.

The home directory contains standard and most frequently used folders: - Videos; - Documents; - Downloads; - Pictures; - Music; - Public; - Templates.

> Users cannot access other users' home directories.

## Screen Lock

If screen lock is configured, after a period of inactivity the user’s desktop is automatically locked using the desktop environment tools (for example: Xfce). To resume work, the user must re-enter authentication credentials:

> The keyboard button allows opening the virtual keyboard.

It is also possible to lock the screen manually through the “Applications Menu” or using keyboard shortcuts:

Utilities for screen locking: - Power Manager ubshutdown-timer Simple power manager - xfce4-session-logout xfce4-session-logout Session logout management utility - dm-tool dm-tool Session management utility - xflock4 xflock4 Bash script for Xfce session locking

Screen lock configuration is performed in the following utilities: - Screensaver xfce4-screensaver-preferences Screensaver and screen lock settings - Power Manager xfce4-power-manager-settings Xfce power manager

> The system also provides power button configuration (power button, suspend, etc.), allowing you to define the action performed when a button is pressed.

## Shutting Down the Computer

To properly shut down (or reboot) the OS during operation, it is not recommended to turn off the power or reboot the computer using the “Reset” button.

`Before shutting down the OS, it is recommended to close all running programs.`

To shut down the OS, you can use several different methods:
1) Navigate to: `Applications Menu > "Log Out" > "Shut Down..."`;
2) Press the key combination `Ctrl`+`Alt`+`Del` to open the system shutdown dialog;
3) Press the key combination `Alt`+`F4` to open the system shutdown dialog;
4) Use the special “shutdown” command in the terminal, available to the root user (superuser).

Clicking the `"Log Out"` button opens a window where you can choose further actions.

## System Settings

To open the settings, go to `Applications Menu > "Settings" tab`, or click the button at the bottom of the applications menu.

> Read more about settings here…

## System Update

> All versions of the UBLinux OS family share a single package repository.
> System updates are saved regardless of the boot mode.

Regular operating system updates play an important role in ensuring security, stability, and compatibility with new software and hardware.

To ensure secure and reliable system operation, regular updates are necessary. System updates:

1) Improve security by adding new features and fixing discovered security vulnerabilities.
2) Enhance system reliability and performance by updating system files and utilities, and fixing known issues.
3) Ensure compatibility with hardware and software by updating drivers, system services, and installed applications.
4) Add new features and capabilities to optimize system performance.

To perform regular OS updates, a network connection is required.

System updates can be performed using both graphical and terminal utilities:

- System Update

  ## Installing and Removing Applications

In the operating system, applications are represented as `packages`. Each package includes necessary files, libraries, and metadata.

Installing, removing, and updating applications (packages) is done using `package managers`. They automate the package management process, providing simplicity and reliability.

More about package management using both graphical and terminal utilities:

- Package Management

## Saving Changes

When working in sandbox modes, installed packages, configured configuration files, system settings, etc. are `not saved` after a reboot.

While working in the “Sandbox with user profile saved to HDD” mode, installed modules, updates, and changes to the UBLinux configuration file are `saved`.

To save installed packages and other system changes, go to: `Applications Menu > Save Changes`.

> Warning! It is forbidden to update the system between the OS boot and the moment of saving changes.
> System updates must not be included in the save!
> If updates were performed — reboot the computer, make the necessary changes, and save again.
> If changes were saved with updates, see the step “Problems after saving changes”

The “Save Changes” program offers two saving methods:

- To a module (/mnt/livemedia/ublinux-data/modules) – all changes will be saved as a module file (.ubm).
- To the system changes directory (/mnt/livemedia/ublinux-data/rootcopy) – saves a set of changed system files and directories to the rootcopy directory.

> When saving all system changes to “/modules”, subsequent system changes should be saved the same way (not to /rootcopy), because rootcopy has the highest priority. Read more…

Example of saving an installed package:

1. Update the database and install a package: `sudo pacman -Sy ciano`

2. Open the program: `Applications Menu > launch "Save Changes"`.

1. After selecting the save method (e.g. to: /ublinux-data/modules), choose the required save mode (e.g. All system changes) and click “Save”.

- Saving Changes More about the utility and how to install it