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32 .\" @(#)hosts.5 8.2 (Berkeley) 12/11/93
40 .Nd host name data base
44 file contains information regarding
45 the known hosts on the network.
46 It can be used in conjunction with DNS, and the NIS
47 maps `hosts.byaddr' and `hosts.byname', as controlled by
49 For each host a single line should be present
50 with the following information:
51 .Bd -unfilled -offset indent
57 Items are separated by any number of blanks and/or
59 A ``#'' indicates the beginning of
60 a comment; characters up to the end of the line are
61 not interpreted by routines which search the file.
63 This file provides a backup used when the name server
65 For the name server, it is suggested that only a few addresses
66 be included in this file.
67 These include addresses for the local interfaces that
69 needs at boot time and a few machines on the local network.
71 This file may be created from the official host
72 data base maintained at the Network Information Control
75 though local changes may be required
76 to bring it up to date regarding unofficial aliases
78 As the data base maintained at
80 is incomplete, use of the name server is recommended for
85 Network addresses are specified in the conventional
86 ``.'' (dot) notation using the
89 from the Internet address manipulation library,
91 Host names may contain any printable
92 character other than a field delimiter, newline,
95 .Bl -tag -width /etc/hosts -compact
103 .Xr gethostbyname 3 ,
104 .Xr nsswitch.conf 5 ,
107 .%T "Name Server Operations Guide for BIND"
112 file format appeared in