ntp config tech note

Joel Jaeggli joelja at darkwing.uoregon.edu
Thu May 20 21:00:09 UTC 2004

note that ntpdate is actually depreciated. and at some point you'll have 
to run ntpd to set the time (with the -q flag) then run it again.


On Thu, 20 May 2004, Randy Bush wrote:

> sorry to take you away from discussing spam with an actual
> tech note, but twice this morning i have hit incidents where
> much needed ntp clients were blown.  so, as i was gonna have
> to write it up, i figured i would bore you all with it.
> ---
> ntp config hint
> 2004.05.20
> ntpd will not work if your clock is off my a few minutes.
> it just sits there forever with its finger in its ear.  so,
> at boot, before you start ntpd, use ntpdate to whack your
> system's time from a friendly low-numbered strat chimer.
> do not background ntpdate with -b, because, if it is slow to
> complete, ntpd can't get the port when you try to start it
> next in the boot sequence.  
> if ntpdate takes a minute and thus adds to your boot time,
> then something is wrong anyway; fix it.
> in case your dns resolver is slow, servers are in trouble,
> etc. have an entry for your ntpdate chimer in /etc/hosts.
> yes, i too hate /etc/hosts; but i have been bitten without
> this hack; named is even more fragile than ntpd.
> once ntpdate has run, then and only then, start your ntpd.
> and read all the usual advice on configuration, selection
> and solicitation of chimers with which to peer, ...
> and then, if having accurate time on this host is critical,
> cron a script which runs `ntpq -c peers` and pipes it to a
> hack which looks to be sure that one of the chimers has a
> splat in front of it.  run this script hourly, and scream
> bloody hell via email if it finds problems.
> ---
> now back to your regular spam discussion.  /*
>    yes, spam is an important issue.  but, if your local
>    organization, this mailing list, ... gets swamped with
>    discussions of spam, then the spammers have won.
>    you have to compartmentalize it, in your organization and
>    in the general net culture.  that's why there are
>    separate mailing lists for spam, ddos, and other net crap
>    with which we have to deal.
>    that's why we have more than one mailing list in the
>    world, to compartmentalize so we can focus.
>    */
> randy

Joel Jaeggli  	       Unix Consulting 	       joelja at darkwing.uoregon.edu    
GPG Key Fingerprint:     5C6E 0104 BAF0 40B0 5BD3 C38B F000 35AB B67F 56B2

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