Cavella Services Ltd. - Blog #NTPCavella Services Ltd. - Blog #NTPhttps://www.cavellaservices.com/blogs/tag/ntpFri, 24 Oct 2025 17:31:40 -0700http://zoho.com/sites/<![CDATA[Interpreting ntpq output]]>https://www.cavellaservices.com/blogs/post/Interpreting-ntpq-output

Once again I had to google what a specific character meant (“o”) in the output from ntpq, here’s my output:

pi@ntp1:~ $ ntpq -pn
      remote           refid      st t when poll reach   delay   offset  jitter 
============================================================================== 
o127.127.22.0    .PPS.            0 l   11   16  377    0.000    0.003   0.001 
*129.250.35.251  129.250.35.222   2 u   28   64  357    9.257   -0.738   0.117 
-132.226.210.133 85.199.214.102   2 u   64   64  373   16.422    1.668   0.343 
+139.143.5.30    139.143.45.145   2 u    1   64  377   11.194   -1.658   0.116 
+134.0.16.1      81.187.26.174    2 u   21   64  317   11.198   -0.816   0.068

To save myself time searching for this in the future, here’s an explanation:

REMOTE = The servers and peers specified in the configuration file, from which your host will take time synchronisation

Character that may prefix the remote hostname/IP address:

* indicates the current synchronisation source.

# indicates that the host is selected for synchronisation, but distance from the host to the server exceeds the maximum value.

o indicates that the host is selected for synchronisation and the PPS signal is in use.

+ indicates the host is included in the final synchronisation selection set.

x indicates that the host is the designated false ticker by the intersection algorithm.

. indicates that the host is selected from the end of the candidate list.

– indicates a host discarded by the clustering algorithm.

blank indicates a host is discarded due to high stratum and/or failed sanity checks.

REFID = the current source of synchronisation for the remote host

ST = the stratum level of the remote host

T = types available:

l local (such as a GPS clock)
u unicast (this is the common type)
m multicast
b broadcast
– netaddr (usually 0)

WHEN = number of seconds passed since the remote host response

POLL = polling interval to the remote host, defined with the “minpoll” value in ntp.conf file

REACH = indicates how successful attempts to reach the server are. This is an 8-bit shift register with the most recent probe in the 2^0 position. The value 001 indicates the most recent probe was answered, while 357 indicates one probe was not answered. The value 377 indicates that all the recent probes have been answered.

DELAY = (round trip time) indicates the time (in milliseconds) taken by the reply packet to return in response, to a query sent by the server.

OFFSET = indicates the time difference (in milliseconds) between the server’s clock and the client’s clock. When this number exceeds 128, and the message synchronisation lost appears in the log file

JITTER = indicates the difference in the offset measurement between two samples. This is an error-bound estimate. Jitter is a primary measure of the network service quality.

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