[Dovecot] ntp revisited (so what to do ?)

[Harlan Stenn]

Per wrote:
> Luigi Rosa wrote:
> 
> > Harlan Stenn said the following on 08/05/11 21:58:
> > 
> >> - Start ntd as early as possible
> >> - - "ntpd -g ..." is better than "ntpdate ... ; ntpd ..."
> >> - Wait before starting time-sensitive services
> >> - - As last as possible in the boot sequence, run 'ntp-wait -v', and
> >>     start time-sensitive services after it successfully returns.
> > 
> > What happens if the server starts with a date very far in the past due
> > to hardware clock reset or something like that?
> > 
> > I mean: if a Linux starts with the hardware clock set to 1/1/2000 how
> > much does it take to get the real date?
> 
> ntpd -g will set it immediately. 

Put another way, ntpd needs the system time to be correct to within 68
years.  Assuming that is true, with a good drift file and good
servers/peers and the use of the 'iburst' flag, ntpd will set the clock
and your (real) machine  will be accurate and stable in about 11
seconds' time.

H