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HOSTS(5)                      File Formats Manual                     HOSTS(5)

     hosts - host name data base

     The hosts file contains information regarding the known hosts on the
     network.  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
           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.

     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 10.99                   November 17, 2000                  NetBSD 10.99