HOSTS(5)                  NetBSD File Formats Manual                  HOSTS(5)

     hosts -- host name data base

     The hosts file contains information regarding the known hosts on the net-
     work.  It can be used in conjunction with the DNS, and the NIS maps
     `hosts.byaddr', and `hosts.byname', as controlled by nsswitch.conf(5).

     For each host a single line should be present with the following informa-
           address hostname [alias ...]

     These are:
           address   Internet address
           hostname  Official host name
           alias     Alias host name

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

     When using the name server named(8), or ypserv(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 address 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 data base 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
     unknown hosts.  As the data base maintained at NIC is incomplete, use of
     the name server is recommended for sites on the DARPA Internet.

     As network addresses, both IPv4 and IPv6 addresses are allowed.  IPv4
     addresses are specified in the conventional dot (``.'') notation using
     the inet_pton(3) routine from the Internet address manipulation library,
     inet(3).  IPv6 addresses are specified in the standard hex-and-colon
     notation.  Host names may contain any printable character other than a
     field delimiter, newline, or comment character.

     /etc/hosts  The hosts file resides in /etc.

     gethostbyname(3), nsswitch.conf(5), ifconfig(8), named(8)

     Name Server Operations Guide for BIND.

     The hosts file format appeared in 4.2BSD.

NetBSD 7.1.2                   November 17, 2000                  NetBSD 7.1.2

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