telegraf/plugins/inputs/ntpq/README.md

2.3 KiB
Raw Permalink Blame History

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