HOSTS(5)                  OpenBSD Programmer's Manual                 HOSTS(5)

NAME
     hosts - host name database

DESCRIPTION
     The hosts file contains information regarding the known hosts on the net-
     work.  For each host, a single line should be present with the following
     information:

           Internet address
           Official host name
           Aliases

     Items are separated by any number of blanks and/or tab characters.  A `#'
     indicates the beginning of a comment; characters up to the end of the
     line are not interpreted by routines which search the file.

     The system configuration file resolv.conf(5) controls where host name in-
     formation will be searched for.  The mechanism provided permits the ad-
     ministrator to describe the databases to search; the databases currently
     known include yp(8), DNS and the hosts database.

     When using the name server named(8), this file provides a backup when the
     name server is not running.  For the name server, it is suggested that
     only a few addresses be included in this file.  These include addresses
     for the local interfaces that ifconfig(8) needs at boot time and a few
     machines on the local network.

     This file may be created from the official host database maintained at
     the Network Information Control Center (NIC), though local changes may be
     required to bring it up to date regarding unofficial aliases and/or un-
     known hosts.  As the database maintained at NIC is incomplete, use of the
     name server is recommended for sites on the DARPA Internet.

     Internet addresses are specified using either dot notation (IPv4) or
     colon separated notation (IPv6).  Further information on network address-
     ing is contained in inet(3).  Host names may contain any printable char-
     acter other than a field delimiter, newline, or comment character.

FILES
     /etc/hosts

SEE ALSO
     getaddrinfo(3), gethostbyname(3), getnameinfo(3), inet(3),
     resolv.conf(5), ifconfig(8), named(8)

     Name Server Operations Guide for BIND.

HISTORY
     The hosts file format appeared in 4.2BSD.

BUGS
     A name server should be used instead of a static file.

     Lines in /etc/hosts are limited to BUFSIZ characters (currently 1024).
     Longer lines will be ignored.

OpenBSD 4.7                    January 29, 2008                              1
