Category: NTP

Query NTP in milliseconds and seconds

For small and larger offsets, ntpd will reject the reference time for a while. In the latter case the operation system’s clock will continue with the last corrections effective while the new reference time is being rejected. After some time, small offsets (significantly less than a second) will be slewed (adjusted slowly), while larger offsets will cause the clock to be stepped (set anew). Huge offsets are rejected, and ntpd will terminate itself, believing something very strange must have happened. To query NTP use one of the following commands:

In milliseconds: ntpq -p
In seconds: ntpdc -p

For example:
In milliseconds
root@ntp:~# ntpq -p
remote refid st t when poll reach delay offset jitter
==============================================================================
-chris.magnet.ie 193.120.10.3 2 u 3 64 377 9.274 9.759 5.386
-tbag.heanet.ie .PPS. 1 u 1 64 277 196.163 6.444 5.583
-ec2-54-171-104- 129.242.4.241 2 u 61 64 377 10.696 11.281 4.481
-lanczos.maths.t 140.203.204.77 2 u 65 64 376 216.847 -0.980 4.405
+ntp1.tp.pl .ATOM. 1 u 60 64 377 242.321 -1.206 1.913
*tshirt.heanet.i .PPS. 1 u 61 64 377 218.342 -5.035 3.481
+time1.google.co 204.153.230.130 2 u 57 64 377 150.045 -1.029 2.885
-time2.google.co 224.240.179.50 2 u 58 64 377 163.618 -3.737 1.734

In seconds:
root@ntp:~# ntpdc -p
remote local st poll reach delay offset disp
=======================================================================
=time1.google.co 2001:470:1c:d7a 2 64 377 0.15004 -0.001029 0.06841
=ec2-54-171-104- 192.168.1.44 2 64 377 0.00960 0.009266 0.04362
=lanczos.maths.t 2001:470:1c:d7a 2 64 377 0.21426 0.014209 0.04640
*tbag.heanet.ie 2001:470:1c:d7a 1 64 277 0.19615 0.006444 0.05617
=ntp1.tp.pl 2001:470:1c:d7a 1 64 377 0.22079 0.005051 0.03702
=tshirt.heanet.i 2001:470:1c:d7a 1 64 377 0.20105 0.005399 0.04185
=time2.google.co 2001:470:1c:d7a 2 64 377 0.16360 -0.003737 0.07126
=chris.magnet.ie 192.168.1.44 2 64 377 0.00926 0.009759 0.04625

NTPQ command.

The ntpq utility program is used to monitor NTP daemon ntpd operations and determine performance. The program can be run either in interactive mode or controlled using command line arguments. Type the following command:

$ ntpq -pn ntp.4network.eu
ntp.4network.eu
remote refid st t when poll reach delay offset jitter
==============================================================================
#204.2.134.164 204.2.134.162 3 u 238 1024 377 185.977 0.415 7.099
-138.236.128.112 18.26.4.105 2 u 42 1024 377 123.400 1.895 1.691
-38.229.71.1 204.123.2.72 2 u 589 1024 377 124.355 5.031 1.320
*134.226.81.3 .GPS. 1 u 163 1024 377 12.422 0.175 3.552
-193.0.71.133 212.244.36.228 2 u 286 1024 377 73.360 4.239 2.494
-198.123.30.132 .GPS. 1 u 824 1024 377 179.881 9.097 4.242
+80.50.231.226 .ATOM. 1 u 917 1024 377 51.067 0.670 4.920
+217.96.29.26 .ATOM. 1 u 312 1024 377 53.215 0.389 0.814
-91.189.94.4 193.79.237.14 2 u 296 1024 377 30.870 5.167 2.027
+131.188.3.221 .DCFp. 1 u 390 1024 377 66.069 2.353 2.582
-193.1.219.116 .PPS. 1 u 923 1024 377 11.893 2.986 4.136
#216.239.32.15 149.48.60.162 2 u 484 1024 377 40.224 -6.111 3.703
#216.239.34.15 21.68.183.109 2 u 926 1024 377 35.171 -3.976 3.364