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32 .\" @(#)hosts.5 8.2 (Berkeley) 12/11/93
33 .\" $FreeBSD: src/share/man/man5/hosts.5,v 1.10 2004/07/03 18:29:22 ru Exp $
34 .\" $DragonFly: src/share/man/man5/hosts.5,v 1.2 2003/06/17 04:37:00 dillon Exp $
41 .Nd host name data base
45 file contains information regarding
46 the known hosts on the network.
47 It can be used in conjunction with DNS, and the NIS
48 maps `hosts.byaddr' and `hosts.byname', as controlled by
50 For each host a single line should be present
51 with the following information:
52 .Bd -unfilled -offset indent
58 Items are separated by any number of blanks and/or
60 A ``#'' indicates the beginning of
61 a comment; characters up to the end of the line are
62 not interpreted by routines which search the file.
64 When using the name server
66 this file provides a backup used when the name server
68 For the name server, it is suggested that only a few addresses
69 be included in this file.
70 These include addresses for the local interfaces that
72 needs at boot time and a few machines on the local network.
74 This file may be created from the official host
75 data base maintained at the Network Information Control
78 though local changes may be required
79 to bring it up to date regarding unofficial aliases
81 As the data base maintained at
83 is incomplete, use of the name server is recommended for
88 Network addresses are specified in the conventional
89 ``.'' (dot) notation using the
92 from the Internet address manipulation library,
94 Host names may contain any printable
95 character other than a field delimiter, newline,
98 .Bl -tag -width /etc/hosts -compact
106 .Xr gethostbyname 3 ,
107 .Xr nsswitch.conf 5 ,
111 .%T "Name Server Operations Guide for BIND"
116 file format appeared in