# Linux System Variables Date, time, language # Locale, Date & Time ### Locale In Linux, a locale is a set of environment variables that defines the language, country, and character encoding settings for a user's environment. Locales affect various aspects of a program's behavior, such as the way dates and times are displayed, the format of numbers, the sort order of strings, and the language used for messages. \------------------------------------------------------------------------------------------------------------------------------------------------ #### View locale configuration ``` localectl ``` and ``` locale ``` View specific locale variable option ``` locale LC_NUMERIC ``` View available locales ``` localectl list-locales ``` \------------------------------------------------------------------------------------------------------------------------------------------------ ##### Setting locale ``` localectl set-locale LANG=fr_FR.utf8 ``` (reboot may be required) ==================================================================================== ### Time \------------------------------------------------------------------------------------------------------------------------------------------------ ##### Check system time ``` date ``` or for more detail ``` timedatectl ``` \------------------------------------------------------------------------------------------------------------------------------------------------ #### NTP ##### View current NTP configuration: ``` timedatectl show-timesync --all ``` ##### Enable NTP ``` timedatectl set-ntp on ``` ##### Disable NTP ``` timedatectl set-ntp off ``` ##### NTP Server selection Most mainstream Linux distributions come with NTP servers preconfigured, these can be altered however, this is done via the /etc/systemd/timesync.conf file. Simply add a new line to the file formatted as follows: ``` NTP=NTPSERVERHOSTNAME ``` \------------------------------------------------------------------------------------------------------------------------------------------------ #### Timezone ##### Check available timezones ``` timedatectl list-timezones ``` ##### Set server timezone ``` timedatectl set-timezone timezonename ``` \------------------------------------------------------------------------------------------------------------------------------------------------ # Hostname ##### Show current server hostname: ``` hostname ``` ##### Show current server hostname, and other useful info: ``` hostnamectl status ``` *example output:* ``` root@test:~# hostnamectl status  Static hostname: test        Icon name: computer-vm          Chassis: vm       Machine ID: 8c1d97558b594586af68685af4a049c9          Boot ID: c2478c600d2b43f0bf58682f1df01013   Virtualization: kvm Operating System: Ubuntu 22.04.3 LTS           Kernel: Linux 5.15.0-106-generic     Architecture: x86-64  Hardware Vendor: QEMU   Hardware Model: Standard PC _i440FX + PIIX, 1996_ ``` Change server hostname: