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NTPTRACE(8) BSD System Manager's Manual NTPTRACE(8) NAME
ntptrace -- trace a chain of NTP servers back to the primary source SYNOPSIS
ntptrace [-vdn] [-r retries] [-t timeout] [server] DESCRIPTION
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 'WWVB' 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 mea- sured by ntptrace ; this is why it is not always zero for localhost ), the host synchronization distance, and (only for stratum-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 syn- chronization distance is the estimated error relative to the primary source. These terms are precisely defined in RFC-1305. OPTIONS
-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 down. -r retries Sets the number of retransmission attempts for each host (default = 5). -t timeout Sets the retransmission timeout (in seconds) (default = 2). -v Prints verbose information about the NTP servers. AUTHORS
David L. Mills (mills@udel.edu) BUGS
This program makes no attempt to improve accuracy by doing multiple samples. BSD
March 29, 2000 BSD