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HOSTS(5) File Formats Manual HOSTS(5) NAME hosts - host name data base DESCRIPTION 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 information: 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 file. 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. FILES /etc/hosts The hosts file resides in /etc. SEE ALSO gethostbyname(3), nsswitch.conf(5), ifconfig(8), named(8) Name Server Operations Guide for BIND. HISTORY The hosts file format appeared in 4.2BSD. NetBSD 9.99 November 17, 2000 NetBSD 9.99