Re: How to use ntp/ntpdate to fix my clock
> Henrique M Holschuh wrote:
> >
> > On Tue, 15 Feb 2000, Patrick Dahiroc wrote:
> > >already on Feb 15, 2000. digging through the package database i came across
> > >ntp and ntpdate and installed both (i have an always on connection to the
> >
> > ntpdate is used to do a "one time only" update to your clock. ntp is used to
> > discipline your clock and will in fact keep the RTC in a short leash
> > updating it every 11 minutes.
>
It is my understanding that this is not true any more. It used to be true but
I believe that updating the bios clock every 11 min by the kernel is not done
any more. Instead, only the kernel (=system) time is kept according to the time
server. The current situation, if I get it correctly, is that
/etc/init.d/hwclock
takes care of writing the system clock to the bios just before that system
goes down.
>
> I don't believe ntp is what Patrick needs. "ntp" is the daemon, i.e.
> the server. "ntpdate" is the "client software". I think what Patrick
> wants is ntpdate and info on available public servers to access, not
> to setup his own ntp server for a sub-net of others.
My understanding is that ntpd (the "daemon"?) can be used as a "client" as
well as a "server" depending on its configuration. The reason for this is that
most sites do get their time from another site, thus they are always
"clients". They may spread their time to other sites, thus making them also a
"server". The important
thing is that they received the time from another site first. Thus, having a
constant network connection makes one to run ntp daemon.
> The info you want Patrick is in ntp-doc, at least. ntp-doc is docs
> in HTML form. They include a link to a list on the net of public
> primary and secondary servers (I'm pretty sure this list can be found
> elsewhere in ntpdate or ntp-doc packages). For most of us, we should
> access a secondary server, there is no reason for an "end-user" like
> us to be using primary servers. I seem to remember also that some
> primary servers require "permission to access" first. Get to that
> list, write down 3-4 of the secondary servers that are geographically
> close, and plug that info into ntpdate's config file.
>
That is tons of docs. But one can only skim it briefly if he installs the
debian package, needs to worry about one machine only, have a constant network
connection and have a server on his network. I am also not sure if one is not
better off using a 3rd or 4th level server in case the network he is on has
one, instead of looking the docs for a geographically closer server.
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