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HOSTS(5)                    BSD File Formats Manual                   HOSTS(5)

     hosts -- host name database

     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

           Internet address
           Official host name

     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
     information will be searched for.  The mechanism provided permits the
     administrator to describe the databases to search; the databases cur-
     rently known include yp(8), DNS and the hosts database.

     When using a name server 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.

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


     getaddrinfo(3), gethostbyname(3), getnameinfo(3), inet_addr(3),
     resolv.conf(5), ifconfig(8), nsd(8), unbound(8)

     The hosts file format appeared in 4.2BSD.

     An official host database used to be maintained at the Network Informa-
     tion Control Center (NIC).

     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.

BSD                              May 29, 2017                              BSD