How to read the ntpq output?

Resolution

 remote           refid      st t when poll reach   delay   offset  jitter
==========================================================================
*time.rhl.       8.16.24.15       2 u  972 1024  377   28.066   -0.181   4.126
+dc1.riu.net     15.15.26.3       3 u  467 1024  377  141.664  -23.531   0.140
mighty.poclabs. .STEP.          16 u    - 1024    0    0.000    0.000   0.000
LOCAL(0)        .LOCL.          10 l   32   64  377    0.000    0.000   0.001

• Reachability Columns:

  • remote: IP address or hostname of the NTP server.
  • refid: Reference ID, a code representing the stratum and source of the time information.

• Status Columns:

  • st: Stratum level of the remote server. Lower stratum numbers indicate more accurate time sources.
  • t: Type of the server - 'l' for local, 'u' for unicast, 'm' for multicast, and 's' for symmetric (peer) mode.
  • when: Time since the last successful poll.
  • poll: Polling interval in seconds.

• Offset Columns:

  • reach: Set of eight characters indicating the reachability status of the server (each character represents a 2^i interval where i is the position of the character from left to right).
  • delay: Round-trip delay to the server in milliseconds.
  • offset: Offset between the local clock and the remote server in milliseconds.
  • jitter: A measure of the stability of the clock offset.

• Other Information:

  • reftime: Reference time - the time when the last update was received from the server.
  • org: Timestamp when the request departed the client for the server.
  • rec: Timestamp when the request arrived at the server.
  • xmt: Timestamp when the reply departed the server for the client.

• Association Columns:

  • associd: Association ID.
  • ind: A character indicating the clock synchronization state ('*' for the selected source, '+' for an acceptable source, '-' for a source with high dispersion).