While debugging a client device using ntp client to get it's time from our ntp server, it was shown that the server sometimes 'hickups' it's clock with an offset of 20 seconds or such. The ntpd adjusts within 10-30 minutes, but of course we want to know why this needed and are looking for the cause.
Digging through the logs and documentation, we found out that the logging is at such a level that these time changing events are not reported.
Various settings were attempted: setting
in /etc/ntp.conf and setting the debug option -d in /etc/default/ntp.conf did not have any effect.
Worse: with the last option the ntpd fails at a restart after a timeout of three minutes:
systemd: ntp.service: Failed with result 'timeout'.
I) How can we raise the debug level without failing to start the service? II) What is the best way of the ntpd reporting about it changing the clock and the reason it does?
The first question is worth 50 from my reputation. If the second is answered I'll raise the bonus to 100 before approving the answer.