Preventing ntpd from adjusting time (backwards)

[Tim Judd]

On Tue, Apr 21, 2009 at 3:39 AM, Matthew Seaman <
m.seaman at infracaninophile.co.uk> wrote:

> Mel Flynn wrote:
> > Hi,
> >
> > Some coarse reading of ntpd(8) and ntp.conf(5) doesn't lead me to believe
> it's
> > possible to make ntpd *not* adjust the time. With adjust I don't mean the
> skew
> > operation, but really change the time. Backwards is my primary concern
> but if
> > it can be turned off completely it's fine with me.
> >
> > Reason being dovecot bailing out when this happens:
> > Apr  1 16:18:26 squish ntpd[1353]: time reset -6.711955 s
> >
> > Apr  1 16:18:26 mx1 dovecot: Fatal: Time just moved backwards by 6
> seconds.
> > This might cause a lot of problems, so I'll just kill myself now.
> > http://wiki.dovecot.org/TimeMovedBackwards
> >
>
> This seems to be a bete-noir for the dovecot developer.  Whatever, it is
> a royal pain in the arse, as my mailserver always steps the time
> backwards on each reboot, and then dovecot does it's dying swan thing.
>
> Three choices:
>
>  * Don't run 'ntpd -g' as the documentation tells you is the modern and
>    accepted method.  Instead, run 'ntpdate' as a separate process and
>    run 'ntpd' without the '-g' flag.
>
>  * Don't run dovecot.  Other IMAP servers do not suffer in the same
>    way.
>
>  * Put up with it.  Avoid reboots, and swear at all concerned any time
>    you really do have to reboot.
>
>        Cheers,
>
>        Matthew
>

How about adding ntpdate's provided string to dovecot's required string in
their respective startup rc.d scripts?  This forces dovecot to wait until
ntpdate has been called, assuming time has actually been set/changed, then
dovecot may start?

I'd try that.  :D