Dovecot keeps shutting down

[brauckmiller]

Hello all, I am somewhat new to Linux, but know enough to be dangerous. :)

I an rumming CentOS 5.2 on a Dell XPS 400 with 1 GIG of RAM.
I am running postfix-2.3.3-2.1.el5_2 and dovecot-1.0.7-2.el5

Postfix is running just fine, but dovecot keeps shutting down.

Here is the line from the dovecot log.

dovecot: Dec 01 09:30:00 Fatal: Time just moved backwards by 8 seconds. This might cause a lot of problems, so I'll just kill myself now. http://wiki.dovecot.org/TimeMovedBackwards

So, I checked out the dovecot link provided and it says this:

1. You're running ntpdate periodically. This isn't a good idea.
2. You're using some kind of a virtual server and you haven't configured it right (or it's buggy).

To the best of my knowlege, I am not running ntpdate but I am running ntpd. I do have an active user signed in via GNOME locally as I run an app via the GUI. Does GNOME run ntpdate periodically?
I am definitely not running any virtual server softare.

So, as a work around, I have setup a cron job that simply restars dovecot every 5 minutes, but I'd really like to get this working correctly.

Help me Obi-wan Kanobe... :)

Thanks

Craig

[NedSlider]

How often is dovecot shutting down, or rather, how long will it run for before shutting down?

Is your server losing or gaining time? It sounds like the server is gaining time and then ntpd is syncing the clock backwards 8 seconds to compensate and dovecot doesn't like it.

Can you monitor the server over a given time period to see how much time it gains or loses. Maybe a new cmos battery is in order.

[AlanBartlett]

[quote]Maybe a new cmos battery is in order.[/quote]
Huh? :-?

The battery supplies power to the CMOS NVRAM which contains the hardware RTC, amongst other things. The RTC is irrelevant once the kernel has been loaded (booted) and is running, as it (the kernel) performs all system time keeping internally. The hardware RTC is only used to give the kernel an approximation of the time -- and most RTCs are inaccurate (drift), so that's why we use [i]ntpd[/i] to ensure that our kernel's time is in sync with the rest of the world. (That's also the reason why an invocation of [i]hwclock --systohc[/i] takes place when halting or rebooting a system -- to sync the RTC to a more accurate source, the kernel time which has, in turn, been sync'd to another more accurate time -- the [i]ntpd[/i] server.)

Now if you are thinking about [i]M$[/i]'s finest product, [i]'doze[/i], you would be correct . . .

[brauckmiller]

Well, the odd thing is that this happened on an older Dell Dimension 4550. I chalked that one up to old hardware originally, but now I am obviously rethinking that.

The dovecot daemon will stay up for about 5 hours before it kills itself. The log below is typical of what I see.

dovecot: Dec 01 13:30:00 Fatal: Time just moved backwards by 7 seconds. This might cause a lot of problems, so I'll just kill myself now. http://wiki.dovecot.org/TimeMovedBackwards
dovecot: Dec 01 14:30:00 Error: Time just moved backwards by 5 seconds. I'll sleep now until we're back in present. http://wiki.dovecot.org/TimeMovedBackwards
dovecot: Dec 01 14:30:06 Error: pop3-login: Time just moved backwards by 5 seconds. I'll sleep now until we're back in present. http://wiki.dovecot.org/TimeMovedBackwards
dovecot: Dec 01 14:30:06 Error: imap-login: Time just moved backwards by 5 seconds. I'll sleep now until we're back in present. http://wiki.dovecot.org/TimeMovedBackwards
dovecot: Dec 01 14:30:06 Error: imap-login: Time just moved backwards by 5 seconds. I'll sleep now until we're back in present. http://wiki.dovecot.org/TimeMovedBackwards
dovecot: Dec 01 14:30:06 Error: imap-login: Time just moved backwards by 5 seconds. I'll sleep now until we're back in present. http://wiki.dovecot.org/TimeMovedBackwards
dovecot: Dec 01 14:30:06 Error: pop3-login: Time just moved backwards by 5 seconds. I'll sleep now until we're back in present. http://wiki.dovecot.org/TimeMovedBackwards
dovecot: Dec 01 14:30:06 Error: pop3-login: Time just moved backwards by 5 seconds. I'll sleep now until we're back in present. http://wiki.dovecot.org/TimeMovedBackwards
dovecot: Dec 01 14:30:06 Error: auth(default): Time just moved backwards by 5 seconds. I'll sleep now until we're back in present. http://wiki.dovecot.org/TimeMovedBackwards
dovecot: Dec 01 15:30:00 Error: Time just moved backwards by 3 seconds. I'll sleep now until we're back in present. http://wiki.dovecot.org/TimeMovedBackwards
dovecot: Dec 01 15:30:04 Error: auth(default): Time just moved backwards by 2 seconds. I'll sleep now until we're back in present. http://wiki.dovecot.org/TimeMovedBackwards
dovecot: Dec 01 15:30:04 Error: imap-login: Time just moved backwards by 3 seconds. I'll sleep now until we're back in present. http://wiki.dovecot.org/TimeMovedBackwards
dovecot: Dec 01 15:30:04 Error: imap-login: Time just moved backwards by 3 seconds. I'll sleep now until we're back in present. http://wiki.dovecot.org/TimeMovedBackwards
dovecot: Dec 01 15:30:04 Error: imap-login: Time just moved backwards by 3 seconds. I'll sleep now until we're back in present. http://wiki.dovecot.org/TimeMovedBackwards
dovecot: Dec 01 15:30:04 Error: pop3-login: Time just moved backwards by 3 seconds. I'll sleep now until we're back in present. http://wiki.dovecot.org/TimeMovedBackwards
dovecot: Dec 01 15:30:04 Error: pop3-login: Time just moved backwards by 3 seconds. I'll sleep now until we're back in present. http://wiki.dovecot.org/TimeMovedBackwards
dovecot: Dec 01 15:30:04 Error: pop3-login: Time just moved backwards by 3 seconds. I'll sleep now until we're back in present. http://wiki.dovecot.org/TimeMovedBackwards
dovecot: Dec 01 16:30:00 Fatal: Time just moved backwards by 12 seconds. This might cause a lot of problems, so I'll just kill myself now. http://wiki.dovecot.org/TimeMovedBackwards

I have disabled the sync in the GNOME clock at arount 09:45 today thinking that was the issue, but I just checked and it still shuts down. Additionally, NTPD has been stopped for some time as I thought it was contributing to the problem.

So, i am seeing the same thing on two differnt systems. The only other thing I can think of is following the advice on the dovecot wiki and re-compile the source without the time check or move to another IMAP/POP3 server.

If the latter, does anyone have a good alternative that is easy to setup?

Thanks,

Craig

[billwest]

If all you need is a pop3, then qpopper is a good alternative.

http://www.eudora.com/products/unsupported/qpopper/index.html


Bill.

[rotorboy]

How do you get qpopper to compile?

http://www.centos.org/modules/newbb/viewtopic.php?topic_id=21156

[rsw686]

Try disabling the cpuspeed service.

chkconfig cpuspeed off
service cpuspeed stop

From your description it sounds like you are running dovecot on CentOS installed on the physical box. Or is dovecot running in xen or something similar?