1 .\" $OpenBSD: ntpd.conf.5,v 1.8 2004/11/07 21:42:33 jmc Exp $
3 .\" Copyright (c) 2003, 2004 Henning Brauer <henning@openbsd.org>
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22 .Nd Network Time Protocol daemon configuration file
24 This manual page describes the format of the
27 It has the following format:
29 Empty lines and lines beginning with the
31 character are ignored.
33 Keywords may be specified multiple times within the configuration file.
36 .It Ic listen on Ar address
37 Specify a local IP address or a hostname the
39 daemon should listen on.
40 If it appears multiple times,
42 will listen on each given address.
45 is given as an address,
47 will listen on all local addresses.
49 does not listen on any address by default.
51 .Bd -literal -offset indent
56 .It Ic server Ar address
57 Specify the IP address or the hostname of an NTP
58 server to synchronize to.
59 If it appears multiple times,
61 will try to synchronize to all of the servers specified.
62 If a hostname resolves to multiple IPv4 and/or IPv6 addresses,
64 uses the first address.
65 If it does not get a reply,
67 retries with the next address and continues to do so until a working address
70 .Bd -literal -offset indent
72 server ntp.example.org
75 To provide redundancy, it is good practice to configure multiple servers.
76 In general, best accuracy is obtained by using servers that have a low
78 .It Ic servers Ar address
81 specify the IP address or hostname of an NTP server to synchronize to.
82 If it appears multiple times,
84 will try to synchronize to all of the servers specified.
85 Should the hostname resolve to multiple IP addresses,
87 will try to synchronize to all of them.
89 .Bd -literal -offset indent
94 .Bl -tag -width "/etc/ntpd.confXXX" -compact
105 file format first appeared in