Let me know how it goes. I have had some problems using ntpdate on an ntp server because ntpdate wants to use the port the server is listening on. I can (and have) shutdown the ntp server, updated the time using ntpdate (and saved it to the hwclock), and restarted the ntp server, but I think ntpdate is not as sophisticated as you suppose (though I could be very wrong, please tell me if that is so) because the clients will not update from the server for a time afterward. I assumed they were 'pissed off' because their 'stable' time source just shifted a drastic amount. I think that the ntp server does the gradual time adjustment, but upstream server admins like to know about your use of their server (ntp connection-wise, not ntpdate) or they might block you. Didn't the U block the RTE ntp server from syncing, or am I remembering things that didn't happen again? >>> veldy at veldy.net 05/16/01 11:34AM >>> You only need to make a connection to an ntp server on a periodic basis (and you can script it to initiate a dial-up connection). It doesn't reset your clock, it changes the "speed" of you clock so that it can minimize drift. If you are ahead, it will slow you clock down, if you are behind, it will speed your clock up. I believe it only affects the OS clock, so unless you save your system clock to the hardware clock, the changes are lost. This is an excellent way to do it, as it avoids time discrepencies in databases and file modification times. I my FreeBSD system check time.nist.gov once daily and I haven't seen anything greater than about a 3 second drift on a bad day. Incidentally, on FreeBSD you can do this in a periodic script: #!/bin/sh # /usr/local/etc/periodic/daily/100.ntp-timeadj # If there is a global system configuration file, suck it in. # if [ -r /etc/defaults/periodic.conf ] then . /etc/defaults/periodic.conf source_periodic_confs fi case "$daily_ntp_time_adj_enable" in [Yy][Ee][Ss]) echo "" echo "Adjusting system time against ntp server:" /usr/sbin/ntpdate time.nist.gov rc=0 ;; *) rc=0;; esac exit $rc And then add: # 100.time_adjustment daily_ntp_time_adj_enable="YES" to your /etc/periodic.conf file. I am setting this machine up to run as an ntp server for the other machines on my LAN so that they are all in sync. Tom Veldhouse veldy at veldy.net ----- Original Message ----- From: "Troy Johnson" <Troy.A.Johnson at state.mn.us> To: <tclug-list at mn-linux.org> Sent: Wednesday, May 16, 2001 11:07 AM Subject: Re: [TCLUG] Atomic PC Clock > I know you can use NTP to hook into an upstream time server, but if you aren't connected all the time or you would just like some independence/redundancy, this seems like an inexpensive option. I don't think I will buy one soon, and the only reason I mention it is that I really thought these things were more expensive than $100. > > >>> mend0070 at tc.umn.edu 05/16/01 10:47AM >>> > On Wed, 16 May 2001, Troy Johnson wrote: > > > Anyone use one of these? It might make for a nice cheap NTP server. > > > > Anyone know of Linux drivers for these? > > > > They seem to sell the docs on the serial data exchange with the unit, > > so if there aren't any now that could be remedied. > > > > http://www.radiocontrolledclock.com/noname4.html > > All it does is sync to WWV, I think. You don't need to spend the money, > because IIRC you can already do that over the net (and adjust for > latency). > > -- > "To misattribute a quote is unforgivable." --Anonymous > > _______________________________________________ > tclug-list mailing list > tclug-list at mn-linux.org > https://mailman.mn-linux.org/mailman/listinfo/tclug-list > > _______________________________________________ > tclug-list mailing list > tclug-list at mn-linux.org > https://mailman.mn-linux.org/mailman/listinfo/tclug-list > _______________________________________________ tclug-list mailing list tclug-list at mn-linux.org https://mailman.mn-linux.org/mailman/listinfo/tclug-list