Re: [ntp:questions] Seeking help configuring GPS refclock
> The only thing interleaved modes avoid is the queuing, buffering and > transmission latencies on the local operating system, driver and > interface card. It doesn't suppress errors due to network latencies. Hmmmph. Yes, I see this now. Sorry I was confused earlier. As for the mysterious 8- to 10-msec discrepancy between my GPS clock and Stanford's campus NTP infrastructure, it turns out that Stanford's existing TrueTime GPS clock is old and is being phased out. My clock agrees very closely with a new Meinberg GPS clock which will become the new campus refclock soon. -- Rich Wales / ri...@richw.org / ri...@stanford.edu Wikipedia: http://en.wikipedia.org/wiki/User:Richwales Facebook: http://www.facebook.com/richwales ___ questions mailing list questions@lists.ntp.org https://lists.ntp.org/mailman/listinfo/questions
Re: [ntp:questions] Seeking help configuring GPS refclock
Rich, The only thing interleaved modes avoid is the queuing, buffereing and transmission latencies on the local operating system, driver and interface card. It doesn't suppress errors due to network latencies. These modes were originally designed for space data links where time tag hardware is available and transmission rates are very low and for Ethernet NICs of the PCNET architecture.. Dave Rich Wales wrote: >>Correct; the interleaved modes, both symmetric and broadcast, >>are in the development version now. >> >> > >OK, thanks for clearing that up. > >Am I correct in understanding that interleaved symmetric mode would >be useful if peers are on opposite sides of a cable or DSL modem >infrastructure? > > > ___ questions mailing list questions@lists.ntp.org https://lists.ntp.org/mailman/listinfo/questions
Re: [ntp:questions] NTP stops when client address changes?
David J Taylor wrote: > phil wrote: > [] >> David, > [] >> It's either that (fixed ip) or just use a simple time program that >> you don't have to fuss with like tardis or some generic program to >> grab ntp time. >> By the way, ntp servers are not worth a flip if the pc you are >> running it on is turned on/off daily. >> >> Phil > > NTP clients work just fine on portables with dynamic IP addresses, in my > experience. All you are asking for there is that the clock agrees to > within a second. > > Normally, I would not be turning server PCs on and off daily, of course, > but I just checked on a stratum-1 PC with a GPS source which had been > rebooted a few minutes ago, and NTP was within a millisecond shortly > after the reboot. That should not be surprising. If you have a valid frequency correction saved, NTPD should be able synchronize quite quickly! It's a "warm start"! Cold starts generally need more time to get "tight synch". ___ questions mailing list questions@lists.ntp.org https://lists.ntp.org/mailman/listinfo/questions
Re: [ntp:questions] NTP stops when client address changes?
phil wrote: [] > David, [] > It's either that (fixed ip) or just use a simple time program that > you don't have to fuss with like tardis or some generic program to > grab ntp time. > By the way, ntp servers are not worth a flip if the pc you are > running it on is turned on/off daily. > > Phil NTP clients work just fine on portables with dynamic IP addresses, in my experience. All you are asking for there is that the clock agrees to within a second. Normally, I would not be turning server PCs on and off daily, of course, but I just checked on a stratum-1 PC with a GPS source which had been rebooted a few minutes ago, and NTP was within a millisecond shortly after the reboot. Cheers, David ___ questions mailing list questions@lists.ntp.org https://lists.ntp.org/mailman/listinfo/questions
Re: [ntp:questions] NTP stops when client address changes?
phil wrote: [] > David, > I may have spoken to fast; you might have to set the "network" side > of the router to a fixed address. Leave the DHCP settings alone and > it will still be able vend an ip to another computer or device on the > network that has no fixed ip. Yes, that's what I have. I actually needed to alter the start of dynamic IP addresses to suit my own needs. My wireless portables pick up a dynamic address just as normal (and NTP works correctly). > There are many guides on the net on walking one through the settings > that are router model specific. Even most router manufactures have > the ability to walk you through the settings as a customer service > for free. Phil .. and we've been using these for getting the folk to set the port forwarding for the particular application. Perhaps, in retrospect, getting them to force a fixed IP address for their PCs would have been a good idea as well. Cheers, David ___ questions mailing list questions@lists.ntp.org https://lists.ntp.org/mailman/listinfo/questions
Re: [ntp:questions] NTP stops when client address changes?
"phil" wrote in message news:h5goi5$fj...@news.eternal-september.org... > > "David J Taylor" > wrote in > message news:h%qem.64818$oo7.26...@text.news.virginmedia.com... >> phil wrote: >> [] >>> You can also give the PC a fixed IP address and not worry about DHCP >>> or lease time. >>> Phil >> >> Yes, in this particular application that would be an excellent solution, >> and one I use myself. But here, we are dealing with non-computer people, >> and just getting them to add the port-forwarding to their router (for the >> application, not NTP) is pain enough. Having to get them to reconfigure >> the router for fixed IPs is probablt a little too far! >> >> Cheers, >> David > > David, > The implication is this is a simple standalone pc using a home-style > router. That be the case, no port forwarding is required. There should be > no change required in the router settings with the use of the fixed IP > providing the computer ip and subnet is properly set. You should be able > to point the dns of the fixed ip pc to the ip of the router and it work > fine. > > It's either that (fixed ip) or just use a simple time program that you > don't have to fuss with like tardis or some generic program to grab ntp > time. > > By the way, ntp servers are not worth a flip if the pc you are running it > on is turned on/off daily. > > Phil > David, I may have spoken to fast; you might have to set the "network" side of the router to a fixed address. Leave the DHCP settings alone and it will still be able vend an ip to another computer or device on the network that has no fixed ip. There are many guides on the net on walking one through the settings that are router model specific. Even most router manufactures have the ability to walk you through the settings as a customer service for free. Phil ___ questions mailing list questions@lists.ntp.org https://lists.ntp.org/mailman/listinfo/questions
Re: [ntp:questions] NTP stops when client address changes?
"David J Taylor" wrote in message news:h%qem.64818$oo7.26...@text.news.virginmedia.com... > phil wrote: > [] >> You can also give the PC a fixed IP address and not worry about DHCP >> or lease time. >> Phil > > Yes, in this particular application that would be an excellent solution, > and one I use myself. But here, we are dealing with non-computer people, > and just getting them to add the port-forwarding to their router (for the > application, not NTP) is pain enough. Having to get them to reconfigure > the router for fixed IPs is probablt a little too far! > > Cheers, > David David, The implication is this is a simple standalone pc using a home-style router. That be the case, no port forwarding is required. There should be no change required in the router settings with the use of the fixed IP providing the computer ip and subnet is properly set. You should be able to point the dns of the fixed ip pc to the ip of the router and it work fine. It's either that (fixed ip) or just use a simple time program that you don't have to fuss with like tardis or some generic program to grab ntp time. By the way, ntp servers are not worth a flip if the pc you are running it on is turned on/off daily. Phil ___ questions mailing list questions@lists.ntp.org https://lists.ntp.org/mailman/listinfo/questions
Re: [ntp:questions] NTP stops when client address changes?
phil wrote: [] > You can also give the PC a fixed IP address and not worry about DHCP > or lease time. > Phil Yes, in this particular application that would be an excellent solution, and one I use myself. But here, we are dealing with non-computer people, and just getting them to add the port-forwarding to their router (for the application, not NTP) is pain enough. Having to get them to reconfigure the router for fixed IPs is probablt a little too far! Cheers, David ___ questions mailing list questions@lists.ntp.org https://lists.ntp.org/mailman/listinfo/questions
