timedatex (8) - Linux Manuals

timedatex: D-Bus service for system clock and RTC settings


timedatex - D-Bus service for system clock and RTC settings




timedatex is a D-Bus service that implements the org.freedesktop.timedate1 interface. It can be used to read and set the system clock, the real-time clock (RTC), the system timezone, and enable or disable an NTP client installed on the system. It is a replacement for the systemd-timedated service.

The system clock is read and set with microsecond resolution, the precision is limited mostly by D-Bus latency. When setting the clock to an absolute time, a correction is applied for the time spent in the polkit authorization check. The clock can be also adjusted precisely by an offset.

The RTC is read with a resolution of one second. The hwclock program is used to set the RTC with a high precision, update the estimated drift, and change the UTC/LOCAL setting.

The system timezone is set by creating symlink /etc/localtime to a file in the /usr/share/zoneinfo directory.

NTP units that should be controlled by timedatex need to be listed in text files in /etc/systemd/ntp-units.d and /usr/lib/systemd/ntp-units.d directories. The first valid unit from the files sorted by name can be enabled/disabled and started/stopped. Other NTP units will be disabled and stopped.


Miroslav Lichvar <mlichvar [at] redhat.com>