On Fri, Apr 24, 2020, 09:27 Per Jessen <per@computer.org> wrote:
Michael Hirmke wrote:

> Hi *,
> I tried to understand the relation between chrony, timedatectl, dhcp
> and NetworkManager on my Tumbleweed notebook.
> I regularily use a LAN connection, WiFi connections and LTE
> connections. In every case the network information is fetched via
> dhcp. Do I need chrony in this environment? Or is the systemd
> timedatectl service sufficient?

That depends on your requirements, how accurate do you need laptop time
to be?  chrony sounds like it would be fine for you.

> If I need chrony, how does chrony get the ntp server address from
> dhcp? I don't want to change it manually in chrony.conf.

The dhcp infos are written to a file, for instance:


contains lines of "variable=value".  Somehow chromy grabs hold of that.

Probably slightly different with NetworkManager.


I do not understand why would you want to change ntp server depending on whichever way you connect to a network. Unless you need local ntp on lan(s) and different one elsewhere.

I personally do not need better time precision than ~ 1s to keep make happy when using network storage - for that any pool.ntp.org is good enough and it works everywhere, including LTE.

Am I missing something?