2.11BSD/man/cat8/ntp.0
NTP(8) UNIX Programmer's Manual NTP(8)
NAME
ntp - query an ntp clock
SYNOPSIS
ntp [-v] [-s] [-f] _h_o_s_t_s...
DESCRIPTION
_n_t_p sends an ntp packet to the ntp daemon running on each of
the given hosts. A daemon fills in fields of the ntp packet
as per RFC-???? and sends the packet back. _n_t_p then for-
mats and prints the result on the standard output.
The default output shows the delay, offset, and date in
_c_t_i_m_e() format.
Options can reset the time of the local system clock.
OPTIONS
-v Verbose output, showing the full contents of received
ntp packets, plus caluclated offset, displacement, etc.
-s Set system time-of-day clock. Will only happen if time
offset is less than compiled-in constant WAYTOBIG
(currently 1000 seconds). Will not happen if remote
host is unsynchronized.
-f Force setting system clock regardless of offset. Must
be used with -s option. Still will not reset clock if
remote system is unsynchronized.
NTP RESULTS
The default output for each _h_o_s_t looks like this:
128.8.10.1: delay:1.845207 offset:-0.358460 Mon Mar 20 08:05:44 1989
The verbose output for each _h_o_s_t looks like this:
Packet from: [128.8.10.1]
Leap 0, version 1, mode Server, poll 6, precision -10 stratum 1 (WWVB)
Synch Distance is 0000.1999 0.099991
Synch Dispersion is 0000.0000 0.000000
Reference Timestamp is a7bea6c3.88b40000 Tue Mar 7 14:06:43 1989
Originate Timestamp is a7bea6d7.d7e6e652 Tue Mar 7 14:07:03 1989
Receive Timestamp is a7bea6d7.cf1a0000 Tue Mar 7 14:07:03 1989
Transmit Timestamp is a7bea6d8.0ccc0000 Tue Mar 7 14:07:04 1989
Input Timestamp is a7bea6d8.1a77e5ea Tue Mar 7 14:07:04 1989
umd1: delay:0.019028 offset:-0.043890 Tue Mar 7 14:07:04 1989
The various fields are interpreted as follows:
Packet from: [_a_d_d_r_e_s_s]
The address that this ntp packet was received from.
Leap indicator: _n
The leap second indicator. Non-zero if there is to be
Printed 4/11/100 30 July 1988 1
NTP(8) UNIX Programmer's Manual NTP(8)
a leap second added or subtracted at the new year.
Status: _n
Stratum: _n (_s_o_u_r_c_e)
The stratum of the clock in the NTP hierarchy, along
with the source of the clock, either the name of a
reference standard (such as WWVB or GOES) or the Inter-
net address of the clock that this clock is derived
from.
Poll = _n
The desired poll rate of the peer.
Precision = _e_x_p_o_n_e_n_t (dec)
The claimed precision of the clock, in seconds.
Synchronizing Dist is ???
Synchronizing Dispersion is ???
The next five timestamps are given as NTP fixed-point
values, in both hexadecimal and _c_t_i_m_e(_3). These are set
either by this ntp process, or by the server we are quering.
Reference Timestamp is _h_e_x-_t_i_m_e_s_t_a_m_p _c_t_i_m_e _s_t_r_i_n_g
The last time the server clock was adjusted. (remote
time)
Originate Timestamp is _h_e_x-_t_i_m_e_s_t_a_m_p _c_t_i_m_e _s_t_r_i_n_g
When the ntp request was transmitted by us to the
server. (local time)
Receive Timestamp is _h_e_x-_t_i_m_e_s_t_a_m_p _c_t_i_m_e _s_t_r_i_n_g
When the ntp request was received at the server.
(remote time)
Transmit Timestamp is _h_e_x-_t_i_m_e_s_t_a_m_p _c_t_i_m_e _s_t_r_i_n_g
When the ntp response was transmitted by the server.
(remote time)
Input Timestamp is _h_e_x-_t_i_m_e_s_t_a_m_p _c_t_i_m_e _s_t_r_i_n_g
When the ntp response was received by us. (local time)
_h_o_s_t_n_a_m_e: delay:_t_i_m_e offset:_t_i_m_e
The summary of the results of the query, giving the
hostname of the responding clock (from the command
line), the round-trip delay, and the offset between the
two clocks (assuming symmetric round-trip times).
Printed 4/11/100 30 July 1988 2
NTP(8) UNIX Programmer's Manual NTP(8)
BUGS
Using _n_t_p with the current host will show inaccurate
results.
Probably a few others. Report bugs to Louis A. Mamokos
(louie@trantor.umd.edu).
SEE ALSO
RFC-???? _N_e_t_w_o_r_k _T_i_m_e _P_r_o_t_o_c_o_l(1), Dave Mills and ...
ntpd(8), ntpdc(8)
Printed 4/11/100 30 July 1988 3