Re: [ntp:questions] reading loopstats file, converting day and time
On 23 Jan, 03:18, anna_chen...@yahoo.com wrote: Hi, I need some help in interpreting the loopstats file, hope someone can help I have ntp configured so that it is generating the loopstats file, the file format is the following 54854 852.338 0.000779917 -85.871689 0.001363577 15.650605 10 54854 2390.510 -0.00876 -85.871689 0.000993395 13.553822 10 checking the linkhttp://www.ntp.org/ntpfaq/NTP-s-trouble.htm the entries represent day, second, offset, drift compensation, estimated error, stability, polling interval I hadn't looked at that perticular webpage until I saw your post, but there is more information on David Mills's website at http://www.eecis.udel.edu/~mills/ntp/html/monopt.html The page includes a table listing the fields in the loopstats file and I think the descriptions of the fields are more helpful in that table. loopstats Record clock discipline loop statistics. Each system clock update appends one line to the loopstats file set: 50935 75440.031 0.06019 13.778 0.000351733 0.013380 6 ItemUnits Description 50935 MJD date 75440.031s Time past midnight 0.06019 s Clock offset 13.778 PPM Frequency offset 0.000351733 s RMS jitter 0.013380PPM RMS wander 6 log2(s) Clock discipline loop time constant [Crossing my fingers and hoping that Google Groups preserves the spacing above.] I assumed the offset is the same offset as in ntpq -p in millisecond and the drift compensation is the same output as drift file for clock frequency error, but what are estimated error, stability and polling interval ? What are the unit of measurement? which output will be useful for monitoring potential problems? The Jitter (estimated error) is defined in the draft RFC for NTP as the root-mean-square (RMS) average of the most recent offset differences, represents the nominal error in estimating the offset. The Wander (stability) is described as the RMS of exponentially weighted frequency differences, so it is a measure of variation in the drift. Bill Unruh already explained the polling interval metric to you. What tool are you using to analyse and graph the loopstats? Mike ___ questions mailing list questions@lists.ntp.org https://lists.ntp.org/mailman/listinfo/questions
Re: [ntp:questions] refid 'STC ' ? What does STC signify?
phr...@gmail.com wrote in message news:bef5f066-1c61-4ff4-8cc0-c0cfad9ec...@n33g2000pri.googlegroups.com... [...] So other than using ntptrace to see if the refclock is reported as an upstream server (an unlikely stratum 0) or something else, there's really no way to know what the heck it is in reality. I can't say that idea gives me a warm, fuzzy feeling. And you are totally right. Trust is hard on the Internet. It is often best established out-of-band. Ntptrace can help, though. Correct me if I'm wrong, but my non-caffeinated brain is telling me someone driven by a budget could set up a server using nothing but it's LCL clock as a source but fudge the ID to be something else. On an isolated network, there'd be no way to detect this (assuming for this academic argument you don't wear a reasonably accurate watch). I can imagine a group of such servers peering with each other endlessly hunting around themselves. Again, you're completely right. (You were already told you look decidedly non-stupid, right?) However, if you're caught in such an isolated network, you're probably close enough that (a) you _can_ detect your situation, and (b) you know who to walk up to and throw The Book[0] at. If ntpd came with a fixStupidNtpConf.ss script, I'd feel better about this. That's actually very easy. Configure three Pool servers. It's really hard to do worse with that than with any recogniseably stupid configuration. On the other hand, if you have the intelligence to recognise your configuration as stupid, you can probably also do better than the Pool. Groetjes, Maarten Wiltink [0] The NTP Book, that is. There is one. His Timeliness Dave Mills wrote it. ___ questions mailing list questions@lists.ntp.org https://lists.ntp.org/mailman/listinfo/questions
[ntp:questions] ntpdate works, but ntpd doesn't (reach = 0)
I am trying to sync to a ntp server. When a do an ntpdate -bu timeServer .. it seems to work fine. I start the ntpd .. and when I do an ntpq -p everything is 0 out.. How can I find out why the ntpdate works, but the ntpd doesn't.. I looked at the server's ntp.conf and is not restricting any queries.. Thanks ___ questions mailing list questions@lists.ntp.org https://lists.ntp.org/mailman/listinfo/questions
Re: [ntp:questions] ntpdate works, but ntpd doesn't (reach = 0)
On 2009-01-22, Lizvette Malave lizvette_mal...@raytheon.com wrote: I am trying to sync to a ntp server. When a do an ntpdate -bu timeServer .. it seems to work fine. I start the ntpd .. and when I do an ntpq -p everything is 0 out.. The -u option tells ntpdate to use a random high port instead of the NTP port (123/UDP). Something is blocking incoming connections on the NTP port. -- Steve Kostecke koste...@ntp.org NTP Public Services Project - http://support.ntp.org/ ___ questions mailing list questions@lists.ntp.org https://lists.ntp.org/mailman/listinfo/questions
[ntp:questions] Garmin GPS 18x LVC no soldering required
I came across a guy selling GPS 18x LVC with a DB-9 cable soldered on by him for use with some data collection device I know nothing about [1]. He's connected the power as well as the serial data lines to the DB-9, which is not what we want for refclock use. I dropped him an email asking if he'd be willing to wire one up with both USB for power and DB-9 to connect to a PC for NTP use. Apparently I wasn't the first to ask, as he responded he's been doing those for $100 plus shipping (and sales tax in California). Now I'm sure some will laugh, but this appeals to me despite the 50% premium over the basic cost of the unit. First off, you need to include the cost of the USB cable and DB-9 connector, then give yourself some budget for your time. I've done my share of soldering over the years and I suck at it, it takes me far too long. I don't trust the hideous-looking results. Put it all together and I'm happy to pay an expert to do it right. [1] http://psn.quake.net/gps/gps18.html Cheers, Dave Hart ___ questions mailing list questions@lists.ntp.org https://lists.ntp.org/mailman/listinfo/questions
Re: [ntp:questions] Garmin GPS 18x LVC no soldering required
Dave Hart daveh...@gmail.com writes: I came across a guy selling GPS 18x LVC with a DB-9 cable soldered on by him for use with some data collection device I know nothing about [1]. He's connected the power as well as the serial data lines to the DB-9, which is not what we want for refclock use. I dropped him an email asking if he'd be willing to wire one up with both USB for power and DB-9 to connect to a PC for NTP use. Apparently I wasn't the first to ask, as he responded he's been doing those for $100 plus shipping (and sales tax in California). Now I'm sure some will laugh, but this appeals to me despite the 50% Why laugh? sounds like a great idea. premium over the basic cost of the unit. First off, you need to include the cost of the USB cable and DB-9 connector, then give yourself some budget for your time. I've done my share of soldering over the years and I suck at it, it takes me far too long. I don't trust the hideous-looking results. Put it all together and I'm happy to pay an expert to do it right. [1] http://psn.quake.net/gps/gps18.html Cheers, Dave Hart ___ questions mailing list questions@lists.ntp.org https://lists.ntp.org/mailman/listinfo/questions
