Home | History | Annotate | Line # | Download | only in etc
ntp.conf revision 1.6
      1  1.6   fredb # $NetBSD: ntp.conf,v 1.6 2003/12/07 16:01:00 fredb Exp $
      2  1.1    fair #
      3  1.1    fair # NetBSD default Network Time Protocol (NTP) configuration file
      4  1.2  simonb # for ntpd
      5  1.1    fair 
      6  1.1    fair # Process ID file, so that the daemon can be signalled from scripts
      7  1.1    fair 
      8  1.3   lukem pidfile		/var/run/ntpd.pid
      9  1.1    fair 
     10  1.2  simonb # The correction calculated by ntpd(8) for the local system clock's
     11  1.1    fair # drift is stored here
     12  1.1    fair 
     13  1.3   lukem driftfile	/var/db/ntp.drift
     14  1.1    fair 
     15  1.1    fair # suppress the syslog(3) message for each peer synchronization change
     16  1.1    fair 
     17  1.3   lukem logconfig	-syncstatus
     18  1.5   fredb 
     19  1.5   fredb # This will help minimize disruptions due to network congestion. Don't
     20  1.5   fredb # do this if you configure only one server!
     21  1.5   fredb 
     22  1.5   fredb tos		minsane 2
     23  1.1    fair 
     24  1.1    fair # Hereafter should be "server" or "peer" statements to configure
     25  1.1    fair # other hosts to exchange NTP packets with. Peers should be selected
     26  1.1    fair # in such a way that the network path to them is symmetric (that is,
     27  1.1    fair # the series of links and routers used to get to the peer is the same
     28  1.1    fair # one that the peer uses to get back. NTP assumes such symmetry
     29  1.1    fair # in its network delay calculation. NTP will apply an incorrect
     30  1.1    fair # adjustment to timestamps received from the peer if the path is not
     31  1.1    fair # symmetric. This can result in clock skew (your system clock being
     32  1.1    fair # maintained consistently wrong by a certain amount).
     33  1.1    fair # 
     34  1.1    fair # The best way to select symmetric peers is to make sure that the
     35  1.1    fair # network path to them is as short as possible (this reduces the
     36  1.1    fair # chance that there is more than one network path between you and
     37  1.1    fair # your peer). You can measure these distances with the traceroute(8)
     38  1.1    fair # program. The best place to start looking for NTP peers for your
     39  1.1    fair # system is within your own network, or at your Internet Service
     40  1.1    fair # Provider (ISP).
     41  1.1    fair #
     42  1.1    fair # Ideally, you should select at least three other systems to talk
     43  1.1    fair # NTP with, for an "what I tell you three times is true" effect.
     44  1.1    fair #
     45  1.1    fair 
     46  1.3   lukem #peer		an.ntp.peer.goes.here
     47  1.3   lukem #server		an.ntp.server.goes.here
     48  1.4     agc 
     49  1.6   fredb # Public servers from the pool.ntp.org project. Volunteer's servers
     50  1.6   fredb # are dynamically assigned to the CNAMES below via DNS round-robin.
     51  1.6   fredb # The pool.ntp.org project needs more volunteers! The only criteria to
     52  1.6   fredb # join are a nailed-up connection and a static IP address. For details,
     53  1.6   fredb # see the web page:
     54  1.6   fredb #
     55  1.4     agc #	http://www.pool.ntp.org/ 
     56  1.6   fredb #
     57  1.6   fredb 
     58  1.6   fredb # The country codes can help you find servers that are net-wise close.
     59  1.6   fredb # As explained above, closer is better...
     60  1.4     agc 
     61  1.6   fredb # Northern U.S.A
     62  1.6   fredb #server		ca.pool.ntp.org
     63  1.6   fredb #server		us.pool.ntp.org
     64  1.6   fredb #server		us.pool.ntp.org
     65  1.6   fredb 
     66  1.6   fredb # Northern Europe
     67  1.6   fredb #server		de.pool.ntp.org
     68  1.6   fredb #server		de.pool.ntp.org
     69  1.6   fredb #server		dk.pool.ntp.org
     70  1.6   fredb 
     71  1.6   fredb # Depending on the vagaries of DNS can occasionally pull in the same
     72  1.6   fredb # server twice. The following CNAMES are guaranteed to be disjoint, at
     73  1.6   fredb # least over some short interval.
     74  1.6   fredb 
     75  1.6   fredb server		0.pool.ntp.org
     76  1.6   fredb server		1.pool.ntp.org
     77  1.6   fredb server		2.pool.ntp.org
     78