systemd systemd-timedated.service 8 systemd-timedated.service systemd-timedated Time and date bus mechanism systemd-timedated.service /usr/lib/systemd/systemd-timedated systemd-timedated.service is a system service that may be used as a mechanism to change the system clock and timezone, as well as to enable/disable network time synchronization. systemd-timedated is automatically activated on request and terminates itself when it is unused. The tool timedatectl1 is a command line client to this service. systemd-timedated currently offers access to the following four settings: The system time The system timezone A boolean controlling whether the system RTC is in local or UTC timezone Whether the time synchronization service is enabled/started or disabled/stopped, see next section. See org.freedesktop.timedate15 and org.freedesktop.LogControl15 for information about the D-Bus API. systemd-timesyncd will look for files with a .list extension in ntp-units.d/ directories. Each file is parsed as a list of unit names, one per line. Empty lines and lines with comments (#) are ignored. Files are read from /usr/lib/systemd/ntp-units.d/ and the corresponding directories under /etc/, /run/, /usr/local/lib/. Files in /etc/ override files with the same name in /run/, /usr/local/lib/, and /usr/lib/. Files in /run/ override files with the same name under /usr/. Packages should install their configuration files in /usr/lib/ (distribution packages) or /usr/local/lib/ (local installs). # /usr/lib/systemd/ntp-units.d/80-systemd-timesync.list systemd-timesyncd.service If the environment variable $SYSTEMD_TIMEDATED_NTP_SERVICES is set, systemd-timesyncd will parse the contents of that variable as a colon-separated list of unit names. When set, this variable overrides the file-based list described above. SYSTEMD_TIMEDATED_NTP_SERVICES=chronyd.service:systemd-timesyncd.service systemd1 timedatectl1 localtime5 hwclock8 systemd-timesyncd8