I ran into an issue when Dovecot fails when ntpd moves time backwards on a Linux server. Here is the message which appears in logs:
dovecot: Fatal: Time just moved backwards by 15 seconds. This might cause a lot of problems, so I’ll just kill myself now. http://wiki.dovecot.org/TimeMovedBackwards
Possible solution here is to add -x flag to ntpd daemon run line. I did that using /etc/sysconfig/ntp file. Now each time ntpd will change time it will do it smoothly.
The root cause of the problem could be an onboard lithium battery. But I hope it’ll solve the problem without taking chassis cover off.
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