Time sync

[Colin Walters]

Hi,

Since http://lists.freedesktop.org/archives/systemd-devel/2015-March/029482.html
systemd-timesyncd can be enabled in more places.  (That change isn't in F22 now
but could be backported easily).   Looking at the state
of things here, there was a previous discussion on the desktop list:
https://lists.fedoraproject.org/pipermail/desktop/2014-September/010751.html

>From an Atomic Host perspective,
systemd-timesyncd now looks fairly equivalent to chrony, and is 140k
that's already shipped.  (Though if systemd didn't do internal static
linking that'd likely be noticeably smaller...anyways, the packaging of
systemd is a separate discussion).

Anaconda looks like it only supports chrony.  Although,
it seems weird that Anaconda itself is doing the bridging of DHCP
NTP servers to chrony config - seems like something to fix in
NetworkManager itself so that it knows how to copy configuration
acquired at install time to the target.

And even then, it seems like we could get away with not setting
the NTP servers persistently from the DHCP lease acquired at
install time, and instead just rely on NM/systemd-networkd to
set them when the system boots again, right?

This however would require NetworkManager -> timesyncd
integration.  Filed that as
https://bugzilla.gnome.org/show_bug.cgi?id=746911

It appears to me that at least Fedora Server has ntp installed
but not running, which (looks) is due to freeipa-client having
a Requires: on ntp.  Which came from
https://fedorahosted.org/freeipa/ticket/2974

Besides gnome-control-center then, I guess the switch of
systemd-timedated to only supporting systemd-timesyncd
impacts FreeIPA too.

But it wouldn't seem that hard for gnome-control-center and
freeipa-client to grow minimal awareness of how to use
systemd-timesyncd's dbus api to set the server.

Currently I'm leaning towards enabling systemd-timesyncd by default
for Atomic Host at least, but sending this mail to get a discussion
across the products.