netdate/ntpdate/ntpd, was: [suse-security] gone - logout
Hi,
nah, you should use ntpdate instead of netdate:
"netdate" will set ANY time it receives and "ntpdate" will validate the time and moves the clock slowly to the right time No, ntpdate gets the time from a time server and sets the clock to the time it just received from the server, no matter how much the difference is. ntpd (or xntpd) behaves like you described it. In the rcscript for ntpd first ntpdate is called once to set the correct time during the boot process, then ntpd is started to keep the time up to date. If you have a running system with a big time difference, and you want to correct it slowly and not at once, do NOT start ntpd using the rcscript, but start it manually (see which command they use in the rcscript in the "start" section). Bye Uli -- Ulrich Roth IMPACT Business & Technology Consulting GmbH Im Mediapark 8 / KölnTurm D-50670 Koeln Phone +49-221-93 70 80-29 Fax +49-221-93 70 80-15 E-Mail: roth@impact.de
* Ulrich Roth <Roth@impact.de> [2003-02-11 09:18 +0100]:
nah, you should use ntpdate instead of netdate: "netdate" will set ANY time it receives and "ntpdate" will validate the time and moves the clock slowly to the right time No, ntpdate gets the time from a time server and sets the clock to the time it just received from the server, no matter how much the difference is.
ntpdate will slew the clock as well, when called with -B. The main difference is the protocol used (netdate:time, ntpdate:ntp). If you're out for security and accuracy, you shouldn't use the old time protocol anyway. For a discussion of the rdate/netdate/nettime/w32time/ntpdate/ntpd tools, see http://www.jfranken.de/homepages/johannes/vortraege/ntpd.en.html -- Johannes Franken Professional unix/network development mailto:jfranken@jfranken.de http://www.jfranken.de/
* Ulrich Roth wrote on Tue, Feb 11, 2003 at 09:18 +0100:
nah, you should use ntpdate instead of netdate:
"netdate" will set ANY time it receives and "ntpdate" will validate the time and moves the clock slowly to the right time
No, ntpdate gets the time from a time server and sets the clock to the time it just received from the server, no matter how much the difference is.
Well, but ntpdate uses NTP protocol, multiple UDP packets, travel-around-timing calculations and so on, in contrast to netdate, which happily sets (time_t)-1, a common error code, as clock. oki, Steffen -- Dieses Schreiben wurde maschinell erstellt, es trägt daher weder Unterschrift noch Siegel.
participants (3)
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Johannes Franken -
Steffen Dettmer -
Ulrich Roth