freebsd-dev/usr.sbin/xntpd/doc/ntptrace.8
1994-04-03 19:50:51 +00:00

105 lines
2.3 KiB
Groff

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.TH NTPTRACE 8 LOCAL
.SH NAME
ntptrace - trace a chain of NTP hosts back to their master time source
.SH SYNOPSIS
.B ntptrace
[
.B -vdn
] [
.B -r
.I retries
] [
.B -t
.I timeout
] [
.I server
]
.SH DESCRIPTION
.I 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.''
.PP
Here is an example of the output from
.IR ntptrace :
.RS 2
.nf
% ntptrace
localhost: stratum 4, offset 0.0019529, synch distance 0.144135
server2.bozo.com: stratum 2, offset 0.0124263, synch distance 0.115784
usndh.edu: stratum 1, offset 0.0019298, synch distance 0.011993, refid 'WWVB'
.fi
.RE
On each line, the fields are (left to right): the host name, the
host's stratum,
the time offset between that host and the local host
(as measured by
.IR ntptrace ;
this is why it is not always zero for ``localhost''),
the host's ``synchronization distance,''
and (only for stratum-1 servers) the reference clock ID. All times
are given in seconds. (Synchronization distance is a measure of the
goodness of the clock's time.)
.SH OPTIONS
.IP "\-d" 5
Turns on some debugging output.
.IP "\-n" 5
Turns off the printing of host names; instead, host IP addresses
are given. This may be necessary if a nameserver is down.
.IP "\-r retries" 5
Sets the number of retransmission attempts for each host; default = 5.
.IP "\-t timeout" 5
Sets the retransmission timeout (in seconds); default = 2.
.IP "\-v" 5
Prints verbose information about the NTP servers.
.SH SEE ALSO
xntpd(8), xntpdc(8)
.SH BUGS
This program makes no attempt to improve accuracy by doing multiple
samples.