[pkg-ntp-maintainers] RFC: Replacing ntpdate with sntp, drop locking

[Bernhard Schmidt]

Hi Kurt (and other interested parties),

I've been thinking about the ifupdown hooks and all the locking we have
in the initscript, the hook (and the systemd-wrapper needs this as well).

As far as I can see the locking is supposed to prevent ntp starting
while ntpdate runs (because ntpdate binds to the priviledged port 123
and ntpd will not start).

First of all, I'd like to change the ntpdate invocation to use sntp
instead of ntpdate (with the appropriate flags). sntp uses unpriviledged
source ports by default, do you see any issue with this? Most other
one-shot clients use random source ports as well (i.e. systemd-timesyncd).

If this default can be used, can we get rid of all the locking?

Bernhard