Meinberg LANTIME, Operating Instructions Manual

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Statistical Information
In the first section a graphical diagram shows the running synchronisation process.
NTP is storing this statistical information in so-called “loopstats” files, which are
used here to draw the curves. The red line is describing the offset between the internal
reference clock (GPS) and the system clock. The blue line shows the frequency errors
of the system time (in PPM, parts per million). In the upper right corner of the
diagram you will find the measurement range of the red and blue curve. The last 24
hours are shown initially, but you are able to select the last 10 days (or fewer days,
depending on the system uptime) or switch to a “merge loopstats” diagram, which
shows all available days in one diagram (with a maximum of 10 days). All time data
is using UTC.
The next sections shows version information for a number of subsystems, including
the OS kernel version, NTPD version and the GPS firmware revision of the internal
reference clock. Additionally, the MAC address of the first Ethernet interface can be
found here. The “Mem free” value is indicating the free memory available to the
system, the Disk free value is related to the ram disk of the LANTIME. Both system
memory and ram disk have a total capacity of 32 MB (each). The Uptime parameter
displays the time since the last boot process of the unit.
In the next section all NTP clients accessing the NTP server are listed. This list is
maintained internally by NTPD, clients who did not access the NTPD for a longer
period are automatically removed. This section can grow very long in large networks.
There are no further information found about the parameters “code, avglen and first.
The name resolution of the IP address in the first colume will take too much time; so
its disabled.
After that a list of all actually refclocks of the internal NTP server will be shown.
remote refid st t when poll reach delay offset jitter
================================================================================
LOCAL(0)
LOCAL(0) 3 l 36 64 3 0.00 0.000 7885
lantime .GPS. 0 l 36 64 1 0.00 60.1 15875
with the following meaning:
- remote:
list of all valid time servers (ntp.conf)
- refid: reference number
- st: actual stratum value (hierarchy level)
- when: last request (seconds)
- poll: period of requesting the time server (seconds)
- reach: octal notation of the successful requests, shifted left
- delay: delay of the network transmission (milliseconds)
- offset: difference between system time and reference time
(milliseconds)
- jitter: variance of the offsets (milliseconds)
The last section will show some NTP specific informations about the refclock.
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