On Sat, May 11, 2013 at 2:48 AM, Richard B. Gilbert <[email protected]> wrote: > On 5/10/2013 10:36 AM, folkert wrote: >> >> Hi, >> >> I have a raspberry pi system. This is a computer without a real time >> clock. So everytime I power it on, it uses starts where it left off >> which might be days earlier. It is connected only very occasionally to >> the internet so syncing to that won't work. It does have, however, a gps >> connected. But as it is switched mostly for less than an hour, ntpd >> won't have the time to adjust the time to what the gps returns to it. >> So I was wondering: is there a utility/a trick out there that picks the >> current time from a gps and then "jumps" the time to what it should be? >> It does not need to be very accurate - a couple of seconds off is ok >> (just not hours or days). >> >> Any ideas? >> >> >> Regards, >> >> Folkert van Heusden >> > > I think you may be out of luck on this one. If you can run NTPD 24x7 > you can have the correct time 24x7. If you can't do this, NTPD is a poor > choice. The problem is that NTPD needs something like ten hours to select a > time source and match the time! > > There is another "product" called "chrony" that has MUCH faster convergence. > I't never used chrony and can't tell you much about it. > > I run 24x7 and seldom have to shut down and restart. >
chrony's convergence is really fast: about a few minutes for a PPS refclock. If you want to run ntpd after, copy the kernel's frequency from ntptime into ntpd's drift file, kill chrony then start ntpd. No need to wait for minutes/hours for ntpd to converge. _______________________________________________ questions mailing list [email protected] http://lists.ntp.org/listinfo/questions
