Open a report at bugs.ntp.org (gmail users probably need to be manually approved because we get far too many spammers opening spam bug reports otherwise) and it will likely be fixed in the upcoming p16.

H

On 9/16/2022 1:16 PM, Edward McGuire wrote:
NTP ntpd 4.2.8p15
Slackware Linux 15.0

It took longer than it should have to figure out that ntpd was not running and 
why. ntpd exited with a panic_stop condition, but there was nothing in syslog. 
Once we understood what happened, it was easy to reproduce. Other messages from 
ntpd were routinely logged, but panic_stop was not logged.

Just to be clear, I understand why we got a panic_stop and I solved that. We 
didn't understand why a fatal error wasn't logged, when other messages, both 
fatal and non-fatal, were logged.

After a good bit of code reading, I decided that the panic_stop message is 
treated much differently from most ntpd messages associated with a fatal 
condition, in two ways.

(1) Messages associated with most fatal conditions are logged, without filtering, before 
the exit() call. But panic_stop is logged only when the syslog filter has 
"+sysevents". Strangely, that's not the out-of-box filter setting.

(2) Messages associated with most fatal conditions have a syslog severity of 3 "error". But panic_stop 
messages have a much lower syslog severity of 6 "info". That is lower even than "notice" which 
means "normal but significant condition".

I can't rely on the default filter setting to log a fatal condition, so as a precaution I turned 
off filtering: "logconfig =allall". Given the importance of fatal conditions, perhaps 
this can be made the out-of-box default, not "logconfig =syncall".

And perhaps the severity associated with the panic_stop message can be changed to "error", not 
"info". An exit() call does not in any useful way leave the ntpd daemon in a "normal but 
significant condition".

But the report_event() routine utilized by the panic_stop condition does not currently 
take a severity as an argument. It simply logs all sysevents at severity 
"info". So this would be kind of a big deal to patch.

I wanted to document this for anyone who might depend on syslog to monitor and 
diagnose problems with ntpd. Also I could have some wrong perceptions about 
what is going on with ntpd logging in general, and panic_stop logging in 
particular, so if you see something, please point it out.

Cheers!
Edward

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Harlan Stenn <st...@nwtime.org>
http://networktimefoundation.org - be a member!
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