''' $Header
''' 
.de Sh
.br
.ne 5
.PP
\fB\\$1\fR
.PP
..
.de Sp
.if t .sp .5v
.if n .sp
..
.de Ip
.br
.ie \\n.$>=3 .ne \\$3
.el .ne 3
.IP "\\$1" \\$2
..
'''
'''     Set up \*(-- to give an unbreakable dash;
'''     string Tr holds user defined translation string.
'''     Bell System Logo is used as a dummy character.
'''
.tr \(bs-|\(bv\*(Tr
.ie n \{\
.ds -- \(bs-
.if (\n(.H=4u)&(1m=24u) .ds -- \(bs\h'-12u'\(bs\h'-12u'-\" diablo 10 pitch
.if (\n(.H=4u)&(1m=20u) .ds -- \(bs\h'-12u'\(bs\h'-8u'-\" diablo 12 pitch
.ds L" ""
.ds R" ""
.ds L' '
.ds R' '
'br\}
.el\{\
.ds -- \(em\|
.tr \*(Tr
.ds L" ``
.ds R" ''
.ds L' `
.ds R' '
'br\}
.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.