[ntp:questions] ntpd: time reset problem

Richard B. Gilbert rgilbert88 at comcast.net
Mon Sep 14 01:17:29 UTC 2009

Brian Utterback wrote:
> Richard B. Gilbert wrote:
>>> Sep 10 20:58:07 seymour ntpd[9104]: synchronized to, 
>>> stratum 1
>>> Sep 10 21:21:02 seymour dovecot: dovecot: Fatal: Time just moved 
>>> backwards by 434 seconds. [ ... ]
>>> Sep 10 21:26:36 seymour ntpd[9104]: no servers reachable
>>> Sep 10 21:42:56 seymour ntpd[9104]: synchronized to, 
>>> stratum 1
>>> Sep 10 21:50:55 seymour ntpd[9104]: time reset +434.824810 s
>> Your clock got yanked around by at least one rogue server!  This sort 
>> of thing is the reason for configuring four, five, or seven servers.
>> It might be helpful if you post your ntp.conf file.
> No, it wasn't yanked by a rogue server. It wasn't yanked by NTP at all. 
> If NTP set the clock backwards, there would be a message that says so. 
> Instead, dovecot notices, and then sometime later NTP notices and puts 
> it back to where it is supposed to be. This isn't an NTP issue at all, 
> it was something external to NTP that yanked the clock.
> Brian Utterback

Okay!  Something jerked the time around and dovecot, whatever that is, 
noticed it and complained.  Twenty-nine minutes later NTPD stepped the 
time to reverse the previous step.

Do you suppose this is another case of someone stepping the time to 
"test" ntpd?

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