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When and how the time is synced via systemd-timedated.service?

Hi,

Does anyone have any ideas about when and how the time is synced via /lib/systemd/system/systemd-timedated.service? (Only once at boot or periodically?)

All help appreciated!

Thank you.

Regards
JJ

Well, maybe this will provide some guidance: https://www.freedesktop.org/software...d.service.html

Quote:

Name

systemd-timedated.service, systemd-timedated — Time and date bus mechanism
Synopsis

systemd-timedated.service

/usr/lib/systemd/systemd-timedated
Description

systemd-timedated is a system service that may be used as a mechanism to change the system clock and timezone, as well as to enable/disable NTP 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 service.

See the developer documentation for information about the APIs systemd-timedated provides.
See Also

systemd(1), timedatectl(1), localtime(5), hwclock(8)

I really don't know about systemd, but I would think that it does essentially what the good old-fashioned way does:

At boot the hardware clock is read and sets the system (software) clock.
NTP is started and synchronizes the system clock.
On shutdown, the synchronized system clock is written to the hardware clock.

Somewhere or other, that same thing has to happen, you'd think.

Hope this helps some.

WatchdogSec=3min
Probably in /lib/systemd/system/dbus-org.freedesktop.timedate1.service
See: http://man7.org/linux/man-pages/man7...ectives.7.html (6,386 lines!)
Maybe line 717 in: https://github.com/systemd/systemd/b...te/timedated.c