Meinberg M900, Руководство по эксплуатации

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CLI NTP Parameter
The NTP configuration page is used to set up the additional NTP parameters
needed for a more specific configuration of the NTP subsystem.
The default configuration of the timeserver consists of a local clock, which represents
the hardware clock of your LANTIME system and the GPS reference clock. The local
clock is only chosen as the NTP time reference after the GPS clock lost its
synchronisation. The stratum level of this local clock is set to 12, this ensures that
clients recognise the switchover to the local clock and are able to eventually take
further actions. The local clock can be disabled.
Because the GPS reference clock is internally connected to the LANTIME system by
using a serial connection, the accuracy using this way of synchronisation is around 1
ms. The high accuracy of the LANTIME timeserver (around 10 microseconds) is
available by using the ATOM driver of the NTP subsystem, which is directly
interpreting the PPS (pulse per second) of the GPS reference clock. The default
configuration looks like this:
# *** lantime ***
# NTP.CONF for GPS167 with UNI ERLANGEN
server 127.127.1.0 # local clock
fudge 127.127.1.0 stratum 12 # local stratum
server 127.127.8.0 mode 135 prefer # GPS167 UNI Erlangen PPS
fudge 127.127.8.0 time1 0.0042 # relative to PPS
server 127.127.22.0 # ATOM (PPS)
fudge 127.127.22.0 flag3 1 # enable PPS API
enable stats
statsdir /var/log/
statistics loopstats
driftfile /etc/ntp.drift
# Edit /mnt/flash/ntpconf.add to add additional NTP parameters
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