"Richard B. Gilbert" <[EMAIL PROTECTED]> writes: >jkvbe wrote: >> Hi, >> >> I've started ntpd with the -x option and defined at run-time (using ntpdc) 3 >> servers. The client machine has an offset of +/- 2s with the ntp servers. >> In the NTP log file I find the following statements (extracted out of a >> total of 98): >> >> 9 Apr 07:46:13 ntpd[19257]: time slew 1.781571 s >> 9 Apr 08:01:16 ntpd[19257]: time slew 1.781200 s >> 9 Apr 08:17:21 ntpd[19257]: time slew 1.781085 s >> 9 Apr 08:32:33 ntpd[19257]: time slew 1.781807 s >> 9 Apr 08:48:37 ntpd[19257]: time slew 1.782273 s >> 9 Apr 09:04:38 ntpd[19257]: time slew 1.781004 s >> 9 Apr 09:19:42 ntpd[19257]: time slew 1.781344 s >> 9 Apr 09:34:46 ntpd[19257]: time slew 1.780407 s >> 9 Apr 09:49:50 ntpd[19257]: time slew 1.778824 s >> >> The times don't seem to converge. >> >> When I shut down the ntp daemon and try to slew the time using ntpdate with >> the -B option it does work. The time difference with the ntp servers >> gradually declines. >> >> We use Suse SLES10 (kernel version: 2.6.16). >> >> Does anybody have an idea on what's going wrong? >> >> Thanks, >> Jan >> >>
>Something is VERY wrong there. It looks as if NTPD is making a massive >correction every fifteen minutes or so! >If you reboot without running NTPD, and set the time manually, how badly >does it drift? If it gains or loses more than something like 43 seconds >per day, NTPD will not work until you get your hardware fixed. Gaining >or losing 1 or 2 seconds per day without NTPD is the expected level of >performance for a typical computer clock. (You get the finest hardware >that $2 US can buy!) Well, no. 1 or 2 sec is 10-20PPM which is on the good side. 43 sec per day is like 500PPM which is definitely on the high side. 5-10sec per day is more typical. Note that chrony(on linux) will fix 43s/day. (It will use the fast slew-- ie changing the tick size-- as well as the slow slew.) ntp as a design decision decided that 500PPM was the max it would ever do. NOt that I advise a computer with 500PPM freq error. something is wrong and is liable to be wrong in more places than just the clock. _______________________________________________ questions mailing list [email protected] https://lists.ntp.org/mailman/listinfo/questions
