On 2007-03-28, [EMAIL PROTECTED] <[EMAIL PROTECTED]> wrote: > We have a setup for a group of Linux machines (2.6.8 kernel,FC3) which > is NOT connected to any outside network. One of the machines has been > made the Time Server. It uses as it's reference the on-board hardware > clock (computer motherboard hardware clock, Real Time Clock (RTC)).
The average quartz wrist watch is a better clock than the on-board RTC. > In NTP terminology this referred to as the Undisciplined local clock. Note the "undisciplined" part. > These machines all perform the same function and has some I/O > cards that causes a heavy interrupt load. The Linux System Clock > is synchronised to the hardware clock yet experiences upto 1 hour > timedrift per month! One way to avoid this drift is to use a dedicated time server system (i.e. one that does nothing but run ntpd). You would need to spend some time calibrating the clock to achieve minimal drift. Another solution is to use a GPS receiver as a ref-clock. A number of us have had good results with the Garmin GPS-18LVC (currently $65.79 + shipping from Provantage). > In any case here is my /etc/ntp.conf file: My comments are unrelated to your clock stability problems. But ... > restrict default nomodify notrap > restrict 127.0.0.1 > server 127.127.1.0 prefer You only have one time source listed so 'prefer' makes no sense. > fudge 127.127.1.0 stratum 0 It is not necessary to fudge the Undicsiplined Local Clock to such a low stratum. Doing this does not make the time "better". > driftfile /var/lib/ntp/drift > broadcastdelay 0.008 > restrict <ipaddres.255> Those last two lines aren't doing anything for you. -- Steve Kostecke <[EMAIL PROTECTED]> NTP Public Services Project - http://ntp.isc.org/ _______________________________________________ questions mailing list [email protected] https://lists.ntp.isc.org/mailman/listinfo/questions
