Hostnamectl

Systemd recognizes that hostnames have grown more varied over the years. The hostnamectl command recognizes three types of hostname with its options: --static is the traditional hostname, used to initialize the system at bootup; --transient is the hostname assigned by a network; and --pretty is the high-level name for humans to read, which may contain many characters that static and transient hostnames are not permitted to use. Then, just to complicate matters further, hostnamectl can also adjust the hostname used in graphical interfaces. For example, set-icon-name NAME sets the hostname displayed on a desktop, and set-chassis TYPE designates a hostname as desktop, laptop, server, tablet, handset, or watch, to affect how they are displayed by some applications.

Use set-hostname NAME to change a hostname, modifying it with an option as necessary. To view the current hostname, use the command status. Add the option --host (-H) to change or view a hostname remotely. Note that a successful name change is marked only by a return to the command prompt.

Localectl

Locales are the languages and settings used for conventions such as currency and time and date formats. Locales typically begin with a two-letter lowercase abbreviation for the language, followed by an underscore and a two-letter uppercase abbreviation for the variant, and ending with an extension that indicates the character encoding – generally, .utf8. For example, en_UK.utf8 stands for the English language as it is used in the United Kingdom. Keyboard maps specify the locale and the keyboard layout, such as Dvorak.

Under systemd, locales are managed by localectl. The localectl command can set the general system locale (set-locale LOCALE), the locale for the X Window system, which includes the general system locale (set-x11-keymaps-variants), and the keyboard locale (set-keymap MAP TOGGLE). If you need to look up locales, you can use the command list-locales for the display or list-keymaps for the keyboard.

Loginctl

To begin using loginctl, run the bare command to receive a list of current logins (Figure 3). If you want details for a session, add the sub-command session-status. Adding the session to a subcommand, you can activate a session, forcing it to replace the one currently displayed – for example, lock-session, unlock-session, terminate-session, or kill-session.

Figure 3: Loginctl controls the accounts logged in to the system.

Besides controlling logins, loginctl can also be used to read what devices are being used by each account with show-user USER and show-seat SEAT.