ntptrace - trace a chain of NTP servers back to the primary source
ntptrace [ -vdn ] [ -r retries ] [ -t timeout ] [ server ]
ntptrace determines where a given Network Time Protocol (NTP) server
gets its time from, and follows the chain of NTP servers back to their
master time source. If given no arguments, it starts with localhost .
Here is an example of the output from ntptrace :
% ntptrace localhost: stratum 4, offset 0.0019529, synch distance
0.144135 server2ozo.com: stratum 2, offset 0.0124263, synch distance
0.115784 usndh.edu: stratum 1, offset 0.0019298, synch distance
0.011993, refid On each line, the fields are (left to right): the host
name, the host stratum, the time offset between that host and the local
host (as measured by ntptrace ; this is why it is not always zero for "
localhost "), the host synchronization distance, and (only for stra-
tum-1 servers) the reference clock ID. All times are given in seconds.
Note that the stratum is the server hop count to the primary source,
while the synchronization distance is the estimated error relative to
the primary source. These terms are precisely defined in RFC-1305.
-d Turns on some debugging output.
-n Turns off the printing of host names; instead, host IP
addresses are given. This may be useful if a nameserver is
-r retries Sets the number of retransmission attempts for each
host (default = 5).
-t timeout Sets the retransmission timeout (in seconds) (default =
-v Prints verbose information about the NTP servers.
This program makes no attempt to improve accuracy by doing multiple
Primary source of documentation: /usr/share/doc/ntp-*/ntptrace.html
David L. Mills <email@example.com>
ntp 4.1.1b-r5 ntptrace(1)
Man(1) output converted with