ntp.conf revision 1.15 1 1.15 christos # $NetBSD: ntp.conf,v 1.15 2013/12/28 03:18:39 christos 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 1.9 reed # A great deal of additional documentation, 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 1.10 christos # Set the number of tries to register with mdns. 0 means never
32 1.10 christos #
33 1.10 christos mdnstries 0
34 1.10 christos
35 1.15 christos # New ntpd disables the ntpdc protocol by default, to re-enable uncomment
36 1.15 christos # the following line
37 1.15 christos # enable mode7
38 1.15 christos
39 1.7 fredb # Hereafter should be "server" or "peer" statements to configure other
40 1.7 fredb # hosts to exchange NTP packets with. Peers should be selected in such
41 1.7 fredb # a way that the network path to them is symmetric (that is, the series
42 1.7 fredb # of links and routers used to get to the peer is the same one that the
43 1.7 fredb # peer uses to get back. NTP assumes such symmetry in its network delay
44 1.7 fredb # calculation. NTP will apply an incorrect adjustment to timestamps
45 1.7 fredb # received from the peer if the path is not symmetric. This can result
46 1.7 fredb # in clock skew (your system clock being maintained consistently wrong
47 1.7 fredb # by a certain amount).
48 1.7 fredb #
49 1.1 fair # The best way to select symmetric peers is to make sure that the
50 1.7 fredb # network path to them is as short as possible (this reduces the chance
51 1.7 fredb # that there is more than one network path between you and your peer).
52 1.7 fredb # You can measure these distances with the traceroute(8) program. The
53 1.7 fredb # best place to start looking for NTP peers for your system is within
54 1.7 fredb # your own network, or at your Internet Service Provider (ISP).
55 1.1 fair #
56 1.7 fredb # Ideally, you should select at least three other systems to talk NTP
57 1.7 fredb # with, for an "what I tell you three times is true" effect.
58 1.1 fair #
59 1.1 fair
60 1.3 lukem #peer an.ntp.peer.goes.here
61 1.3 lukem #server an.ntp.server.goes.here
62 1.4 agc
63 1.6 fredb # Public servers from the pool.ntp.org project. Volunteer's servers
64 1.6 fredb # are dynamically assigned to the CNAMES below via DNS round-robin.
65 1.6 fredb # The pool.ntp.org project needs more volunteers! The only criteria to
66 1.6 fredb # join are a nailed-up connection and a static IP address. For details,
67 1.6 fredb # see the web page:
68 1.6 fredb #
69 1.14 christos # http://www.pool.ntp.org/join.html
70 1.6 fredb #
71 1.6 fredb
72 1.6 fredb # Depending on the vagaries of DNS can occasionally pull in the same
73 1.6 fredb # server twice. The following CNAMES are guaranteed to be disjoint, at
74 1.13 christos # least over some short interval. The following servers are allocated
75 1.13 christos # to the NetBSD project.
76 1.6 fredb
77 1.13 christos server 0.netbsd.pool.ntp.org
78 1.13 christos server 1.netbsd.pool.ntp.org
79 1.13 christos server 2.netbsd.pool.ntp.org
80 1.13 christos server 3.netbsd.pool.ntp.org
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