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ntp.conf revision 1.8
      1  1.8   fredb # $NetBSD: ntp.conf,v 1.8 2003/12/07 16:11:58 fredb Exp $
      2  1.1    fair #
      3  1.7   fredb # NetBSD default Network Time Protocol (NTP) configuration file for ntpd
      4  1.8   fredb 
      5  1.8   fredb # This file is intended to be both a usable default, and a Quick-Start
      6  1.8   fredb # Guide. The directives and options listed here are not at all complete.
      7  1.8   fredb # A great deal of additional documention, including links to FAQS and
      8  1.8   fredb # other guides, may be found on the official NTP web site, in particular
      9  1.8   fredb #
     10  1.8   fredb #	http://www.ntp.org/documentation.html
     11  1.8   fredb #
     12  1.1    fair 
     13  1.1    fair # Process ID file, so that the daemon can be signalled from scripts
     14  1.1    fair 
     15  1.3   lukem pidfile		/var/run/ntpd.pid
     16  1.1    fair 
     17  1.2  simonb # The correction calculated by ntpd(8) for the local system clock's
     18  1.7   fredb # drift is stored here.
     19  1.1    fair 
     20  1.3   lukem driftfile	/var/db/ntp.drift
     21  1.1    fair 
     22  1.7   fredb # Suppress the syslog(3) message for each peer synchronization change.
     23  1.1    fair 
     24  1.3   lukem logconfig	-syncstatus
     25  1.5   fredb 
     26  1.5   fredb # This will help minimize disruptions due to network congestion. Don't
     27  1.5   fredb # do this if you configure only one server!
     28  1.5   fredb 
     29  1.5   fredb tos		minsane 2
     30  1.1    fair 
     31  1.7   fredb # Hereafter should be "server" or "peer" statements to configure other
     32  1.7   fredb # hosts to exchange NTP packets with. Peers should be selected in such
     33  1.7   fredb # a way that the network path to them is symmetric (that is, the series
     34  1.7   fredb # of links and routers used to get to the peer is the same one that the
     35  1.7   fredb # peer uses to get back. NTP assumes such symmetry in its network delay
     36  1.7   fredb # calculation. NTP will apply an incorrect adjustment to timestamps
     37  1.7   fredb # received from the peer if the path is not symmetric. This can result
     38  1.7   fredb # in clock skew (your system clock being maintained consistently wrong
     39  1.7   fredb # by a certain amount).
     40  1.7   fredb #
     41  1.1    fair # The best way to select symmetric peers is to make sure that the
     42  1.7   fredb # network path to them is as short as possible (this reduces the chance
     43  1.7   fredb # that there is more than one network path between you and your peer).
     44  1.7   fredb # You can measure these distances with the traceroute(8)  program. The
     45  1.7   fredb # best place to start looking for NTP peers for your system is within
     46  1.7   fredb # your own network, or at your Internet Service Provider (ISP).
     47  1.1    fair #
     48  1.7   fredb # Ideally, you should select at least three other systems to talk NTP
     49  1.7   fredb # with, for an "what I tell you three times is true" effect.
     50  1.1    fair #
     51  1.1    fair 
     52  1.3   lukem #peer		an.ntp.peer.goes.here
     53  1.3   lukem #server		an.ntp.server.goes.here
     54  1.4     agc 
     55  1.6   fredb # Public servers from the pool.ntp.org project. Volunteer's servers
     56  1.6   fredb # are dynamically assigned to the CNAMES below via DNS round-robin.
     57  1.6   fredb # The pool.ntp.org project needs more volunteers! The only criteria to
     58  1.6   fredb # join are a nailed-up connection and a static IP address. For details,
     59  1.6   fredb # see the web page:
     60  1.6   fredb #
     61  1.4     agc #	http://www.pool.ntp.org/ 
     62  1.6   fredb #
     63  1.6   fredb 
     64  1.6   fredb # The country codes can help you find servers that are net-wise close.
     65  1.6   fredb # As explained above, closer is better...
     66  1.4     agc 
     67  1.6   fredb # Northern U.S.A
     68  1.6   fredb #server		ca.pool.ntp.org
     69  1.6   fredb #server		us.pool.ntp.org
     70  1.6   fredb #server		us.pool.ntp.org
     71  1.6   fredb 
     72  1.6   fredb # Northern Europe
     73  1.6   fredb #server		de.pool.ntp.org
     74  1.6   fredb #server		de.pool.ntp.org
     75  1.6   fredb #server		dk.pool.ntp.org
     76  1.6   fredb 
     77  1.6   fredb # Depending on the vagaries of DNS can occasionally pull in the same
     78  1.6   fredb # server twice. The following CNAMES are guaranteed to be disjoint, at
     79  1.6   fredb # least over some short interval.
     80  1.6   fredb 
     81  1.6   fredb server		0.pool.ntp.org
     82  1.6   fredb server		1.pool.ntp.org
     83  1.6   fredb server		2.pool.ntp.org
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