charles.br...@sensis.com (Charles Brown) writes: > This seems like it should be a common question, but I can't find it >on the Big I.
> I have a processor with a serial GPS on a closed private network. If >the GPS is not locked, or the GPS inputs are missing, I still want the >ntpd to serve *some* time, perhaps from the undisciplined local clock. >I.e., the server can't just do nothing. Does the GPS driver do that >automatically, or do I have to configure two drivers in the ntpd.conf? >Perhaps something like; > prefer peer 127.127.20.u > peer 127.127.1.u This is ONLY true if you want this machine to be a server to other machines, and you want to maintain synchronization even if the GPS disappears. The on board clock will keep its best estimate of the time without anything from ntp. It is ONLY ONLY if those other machines which are using your machine as an ntp server MUST still sync from that server even if the GPS is down that you want to use the 127.127.1.0 as a source. > Suppose I have a second server, with a higher precision oscillator, >on this same network. How would I configure that? Perhaps; > prefer peer morePreciseServer # should be best source No way. The GPS will be better almost always. > peer 127.127.20.u # next is the GPS > peer 127.127.1.u # if all else fails.... > What would the configuration on the other processor look like? Perhaps; What other processor? > prefer peer 127.127.22.u # always best > peer 127.127.1.u # if GPS fails, still better for a NEVER USE THE LOCAL CLOCK unless absolutely necessary. NEVER USE THE LOCAL CLOCK as a server. > # couple of days > peer lessPreciseServer # GPS missing a long time, > # lessPreciseServer might have GPS > Should I coerce stratum values? >--CB _______________________________________________ questions mailing list questions@lists.ntp.org https://lists.ntp.org/mailman/listinfo/questions
