systemd-timedated.service, systemd-timedated - Time and date bus mechanism
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 timedatectl(1) is a command line client to this
systemd-timedated currently offers access to the following four
•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.timedate1(5) and
org.freedesktop.LogControl1(5) for information about the D-Bus
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/
Example 1. ntp-units.d/ entry for
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.
Example 2. An override that specifies that
chronyd should be used if available