Re: [vox] Set the Clock/Time?

[Jeff Newmiller <jdnewmilMAPS@dcn.davis.ca.us>]

On Wed, 19 Sep 2001, Don Werve wrote:

> Henry House wrote:
> > I like 'rdate', which sets the time from an machine on hte net running a time
> > server.
> > 
> > > The command "hwclock" can write the system time into your BIOS clock.
> > > I forget the exact syntax.. check the man page. :)
> > 
> > Most distros run this at reboot and shutdown.
> 
> I use ntpdate and ntpd; ntpdate runs on boot, once, to synchronize the
> time against 
> my NTP server, and than ntpd runs while the system is up to keep the
> clock accurate.
> I have 'hwclock -w' set to run hourly from cron to keep the hardware
> clock in check.

I also use ntpd.  However, there are some issues to consider:

* ntpdate and ntpd both use the ntp protocol, but ntpd runs in the
  background and assumes that you will be connected to the net most of the
  time, if not all the time, while ntpdate finishes when it returns from
  your command-line invocation.

* rdate conforms to RFC868, which is accurate to one second, while
  ntpd converges to accuracies of milliseconds.  ntpdate is between these.

* Being on a dialup line affects use of ntpd, but I have used ntpdate in
  such situations.  Anyway, I see now that the Clock mini-howto looks like
  a more up-to-date review of the current options than my experience
  offers:

    http://www.linuxdoc.org/HOWTO/mini/Clock.html

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