xref: /csrg-svn/share/man/man5/hosts.5 (revision 49644)
1*49644Scael.\" Copyright (c) 1983, 1991 The Regents of the University of California.
236757Sbostic.\" All rights reserved.
320821Smckusick.\"
4*49644Scael.\" %sccs.include.redist.roff%
520821Smckusick.\"
6*49644Scael.\"     @(#)hosts.5	6.6 (Berkeley) 05/10/91
736757Sbostic.\"
8*49644Scael.Dd
9*49644Scael.Dt HOSTS 5
10*49644Scael.Os BSD 4.2
11*49644Scael.Sh NAME
12*49644Scael.Nm hosts
13*49644Scael.Nd host name data base
14*49644Scael.Sh DESCRIPTION
1520821SmckusickThe
16*49644Scael.Nm hosts
1720821Smckusickfile contains information regarding
1828183Sbloomthe known hosts on the network.
1920821SmckusickFor each host a single line should be present
2020821Smckusickwith the following information:
21*49644Scael.Bd -unfilled -offset indent
2220821Smckusickofficial host name
2320821SmckusickInternet address
2420821Smckusickaliases
25*49644Scael.Ed
26*49644Scael.Pp
2720821SmckusickItems are separated by any number of blanks and/or
2820821Smckusicktab characters.  A ``#'' indicates the beginning of
2920821Smckusicka comment; characters up to the end of the line are
3020821Smckusicknot interpreted by routines which search the file.
31*49644Scael.Pp
3228183SbloomWhen using the name server
33*49644Scael.Xr named 8 ,
3428183Sbloomthis file provides a backup when the name server
3528183Sbloomis not running.
3628183SbloomFor the name server, it is suggested that only a few addresses
3728183Sbloombe included in this file.
3828183SbloomThese include  address for the local interfaces that
39*49644Scael.Xr ifconfig 8
4028183Sbloomneeds at boot time and a few machines on the local network.
41*49644Scael.Pp
4228183SbloomThis file may be created from the official host
4320821Smckusickdata base maintained at the Network Information Control
44*49644ScaelCenter
45*49644Scael.Pq Tn NIC ,
46*49644Scaelthough local changes may be required
4720821Smckusickto bring it up to date regarding unofficial aliases
48*49644Scaeland/or unknown hosts.  As the data base maintained at
49*49644Scael.Tn NIC
5028183Sbloomis incomplete, use of the name server is recommend for
51*49644Scaelsites on the
52*49644Scael.Tn DARPA
53*49644ScaelInternet.
54*49644Scael.Pp
5520821SmckusickNetwork addresses are specified in the conventional
56*49644Scael``.'' (dot) notation using the
57*49644Scael.Xr inet_addr 3
58*49644Scaelroutine
5920821Smckusickfrom the Internet address manipulation library,
60*49644Scael.Xr inet 3 .
6120821SmckusickHost names may contain any printable
6220821Smckusickcharacter other than a field delimiter, newline,
6320821Smckusickor comment character.
64*49644Scael.Sh FILES
65*49644Scael.Bl -tag -width /etc/hosts -compact
66*49644Scael.It Pa /etc/hosts
67*49644ScaelThe
68*49644Scael.Nm hosts
69*49644Scaelfile resides in
70*49644Scael.Pa /etc .
71*49644Scael.El
72*49644Scael.Sh SEE ALSO
73*49644Scael.Xr gethostbyname 3 ,
74*49644Scael.Xr ifconfig 8 ,
75*49644Scael.Xr named 8
76*49644Scael.Rs
77*49644Scael.%T "Name Server Operations Guide for BIND"
78*49644Scael.Re
79*49644Scael.Sh HISTORY
80*49644ScaelThe
81*49644Scael.Nm
82*49644Scaelfile format appeared in
83*49644Scael.Bx 4.2 .
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