telegraf/plugins/inputs/ntpq/README.md

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ntpq Input Plugin

Get standard NTP query metrics, requires ntpq executable.

Below is the documentation of the various headers returned from the NTP query command when running ntpq -p.

  • remote The remote peer or server being synced to. “LOCAL” is this local host (included in case there are no remote peers or servers available);
  • refid Where or what the remote peer or server is itself synchronised to;
  • st (stratum) The remote peer or server Stratum
  • t (type) Type (u: unicast or manycast client, b: broadcast or multicast client, l: local reference clock, s: symmetric peer, A: manycast server, B: broadcast server, M: multicast server, see “Automatic Server Discovery“);
  • when When last polled (seconds ago, “h” hours ago, or “d” days ago);
  • poll Polling frequency: rfc5905 suggests this ranges in NTPv4 from 4 (16s) to 17 (36h) (log2 seconds), however observation suggests the actual displayed value is seconds for a much smaller range of 64 (26) to 1024 (210) seconds;
  • reach An 8-bit left-shift shift register value recording polls (bit set = successful, bit reset = fail) displayed in octal;
  • delay Round trip communication delay to the remote peer or server (milliseconds);
  • offset Mean offset (phase) in the times reported between this local host and the remote peer or server (RMS, milliseconds);
  • jitter Mean deviation (jitter) in the time reported for that remote peer or server (RMS of difference of multiple time samples, milliseconds);

Configuration:

# Get standard NTP query metrics, requires ntpq executable
[[inputs.ntpq]]
  ## If false, set the -n ntpq flag. Can reduce metric gather times.
  dns_lookup = true

Measurements & Fields:

  • ntpq
    • delay (float, milliseconds)
    • jitter (float, milliseconds)
    • offset (float, milliseconds)
    • poll (int, seconds)
    • reach (int)
    • when (int, seconds)

Tags:

  • All measurements have the following tags:
    • refid
    • remote
    • type
    • stratum

Example Output:

$ telegraf -config ~/ws/telegraf.conf -input-filter ntpq -test
* Plugin: ntpq, Collection 1
> ntpq,refid=.GPSs.,remote=*time.apple.com,stratum=1,type=u delay=91.797,jitter=3.735,offset=12.841,poll=64i,reach=377i,when=35i 1457960478909556134