[ntp:questions] NTP.conf using Dave Hart code.

Dave Hart davehart at gmail.com
Tue Feb 9 15:20:07 UTC 2010


On Feb 9, 13:53 UTC, BK <bkrei... at sigmatechcorp.com> wrote:
> pps 127.127.22.1 stratum 1

fudge 127.127.22.1 refid pps stratum 1

> gps 127.127.20.1 stratum 2

fudge 127.127.20.1 refid gps stratum 2

But that's not something I'd recommend -- there is no need to fudge
stratum for refclock drivers, and you're going to in fact make the
refid unreadable if you change from stratum 1.  ntpd and ntpq treat
stratum 1 refids as 4 ASCII characters, while higher stratum refids
are displayed as if they were IPv4 addresses (sometimes they're hashed
32-bit numbers derived from IPv6 addresses).

You mentioned using the replacement serialpps.sys driver.  Keep in
mind that the easiest way to use this with a PPS-enabled GPS connected
via serial is to configure only the NMEA driver (20) and leave out the
PPS/atom driver (22).  The details depend on which version of ntpd
you're working with, but the NMEA driver is capable of using PPSAPI to
get high-quality PPS timestamps from serialpps.sys, and in a single-
driver configuration, there is no need for a separate prefer source.

If you do choose to configure both drivers, make sure NMEA isn't
attempting to use PPSAPI and leave that to the PPS/atom driver alone,
and add prefer to the "server 127.127.20.1" line.

Cheers,
Dave Hart

P.S.  Very little of the code in ntpd is "Dave Hart code".  I will
take credit for making up-to-date NTP binaries for Windows available
regularly:  http://davehart.net/ntp/win/x86/




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