Date: Thu, 9 Nov 2000 14:25:16 -0600 From: Dan Nelson <dnelson@emsphone.com> To: Drew Tomlinson <drewt@writeme.com> Cc: "'FreeBSD Questions (E-mail)'" <freebsd-questions@FreeBSD.ORG> Subject: Re: ntpd "Synchronization Lost" Errors Message-ID: <20001109142516.A22141@dan.emsphone.com> In-Reply-To: <BA5D0CE1CBB2D411B6AA00A0CC3F02390AF6FD@ldcmsx01.lc.ca.gov>; from "Drew Tomlinson" on Thu Nov 9 09:08:54 GMT 2000 References: <20001109103846.A18298@dan.emsphone.com> <BA5D0CE1CBB2D411B6AA00A0CC3F02390AF6FD@ldcmsx01.lc.ca.gov>
next in thread | previous in thread | raw e-mail | index | archive | help
In the last episode (Nov 09), Drew Tomlinson said: > > Yow. an offset of 32 seconds is a whole lot. What is the contents > > of /etc/ntp.drift? If it's over 500 or less than -500, ntpd will > > have a hard time keeping your clock in synch because it drifts too > > fast. > > 145 Blacksheep# cat ntp.drift > -500.000 NTP limits drift to 500 ppm, so that means that your clock is probably worse than 500. > > I'd set up a cron job that fires every hour and runs "cat > > /etc/ntp.drift >> /var/log/ntp.drift", and check that log after a > > day or so so see what the trend is. > > So is the ntp.drift file recalculated after every update? I haven't > gotten to cron jobs yet but I guess there's no time like the present. > :) The drift file is updated once an hour, I believe. > I edited my ntp.conf file to point to a different server and > restarted ntpd. I received the following messages in my log file: > > Nov 9 08:59:32 blacksheep ntpd[1546]: ntpd 4.0.99b Mon Nov 6 00:47:01 PST 2000 (1) > Nov 9 08:59:32 blacksheep ntpd[1546]: using kernel phase-lock loop 2040 > Nov 9 08:59:32 blacksheep ntpd[1546]: frequency initialized -500.000 from /etc/ntp.drift > Nov 9 08:59:32 blacksheep ntpd[1546]: using kernel phase-lock loop 2041 > > I don't know exactly what they mean but I didn't get them before. Now I get > the following with ntpdc: You should get those lines every time ntp is started. Another thing you can try is changing your clock source. Add the following lines to your kernel config file and recompile: options CLK_USE_I8254_CALIBRATION options CLK_USE_TSC_CALIBRATION That should calibrate two internal clocks against the CMOS clock, which is usually pretty accurate. -- Dan Nelson dnelson@emsphone.com To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-questions" in the body of the message
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?20001109142516.A22141>