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\input texinfo    @c -*-texinfo-*-
@c %**start of header
@setfilename ntpd.info
@settitle ntpd: Network Time Protocol (NTP) Daemon User's Manual
@include ../sntp/include/version.texi
@paragraphindent 2
@c %**end of header

@ifinfo
This file documents the use of the NTP Project's ntpd, a program for
controlling ntpd.
@end ifinfo

@direntry
* ntpd: (ntpd).                               NTP Daemon program
@end direntry

@titlepage
@title ntpd: Network Time Protocol (NTP) Daemon User's Manual
@subtitle ntpd, version @value{VERSION}, @value{UPDATED}
@c @author Max @email{foo@ntp.org}
@end titlepage

@c @page
@c @vskip 0pt plus 1filll

@node Top, ntpd Description, (dir), (dir)
@top ntpd: Network Time Protocol (NTP) Daemon User Manual

The @code{ntpd} program is an operating system daemon that synchronizes the
system clock to remote NTP time servers or local reference clocks.
It is a complete implementation of NTP version 4 defined by RFC-5905, but
also retains compatible with version 3 defined by RFC-1305 and versions
1 and 2, defined by RFC-1059 and RFC-1119, respectively.
The program can operate in any of several modes, including client/server,
symmetric and broadcast modes, and with both symmetric-key and public-key
cryptography.

This document applies to version @value{VERSION} of @code{ntpd}.

@shortcontents

@menu
* ntpd Description::            Description
* ntpd Invocation::		Invoking ntpd
* Usage::                       Usage
@end menu

@node ntpd Description
@comment  node-name,  next,  previous,  up
@section Description

The @code{ntpd} program ordinarily requires
a configuration file described at @ref{ntp.conf}.
This configuration file contains configuration commands described on
the pages listed above.
However a client can discover remote servers and configure them
automatically.
This makes it possible to deploy a fleet of workstations without
specifying configuration details specific to the local environment.

The @code{ntpd} program normally operates continuously while adjusting the
system time and frequency, but in some cases this might not be
practical.
With the @code{-q} option @code{ntpd} operates as in continuous mode, but
exits just after setting the clock for the first time.
Most applications will probably want to specify the @code{iburst}
option with the @code{server} command.
With this option an initial volley of messages is exchanged to
groom the data and set the clock in about ten seconds' time.
If nothing is heard after a few minutes' time,
the daemon times out and exits without setting the clock.

@include invoke-ntpd.texi

@node Usage
@comment  node-name,  next,  previous,  up
@section Usage

@multitable @columnfractions .23 .23 .05 .15
@headitem What @tab Default @tab Flag @tab Option
@item configuration file
@tab @code{/etc/ntp.conf}
@tab @code{-c}
@tab @code{conffile}
@item frequency file
@tab none
@tab @code{-f}
@tab @code{driftfile}
@item leapseconds file
@tab none
@tab
@tab @code{leapfile}
@item process ID file
@tab none
@tab @code{-p}
@tab @code{pidfile}
@item log file
@tab system log
@tab @code{-l}
@tab @code{logfile}
@item include file
@tab none
@tab none
@tab @code{includefile}
@item statistics path
@tab @code{/var/NTP}
@tab @code{-s}
@tab @code{statsdir}
@item keys path
@tab @code{/usr/local/etc}
@tab @code{-k}
@tab @code{keysdir}