diff options
Diffstat (limited to 'man5/hosts.5')
| -rw-r--r-- | man5/hosts.5 | 107 |
1 files changed, 107 insertions, 0 deletions
diff --git a/man5/hosts.5 b/man5/hosts.5 new file mode 100644 index 000000000..334fee197 --- /dev/null +++ b/man5/hosts.5 @@ -0,0 +1,107 @@ +.\" Hey, Emacs! This is an -*- nroff -*- source file. +.\" Copyright (c) 2000 Manoj Srivastava <srivasta@debian.org> +.\" +.\" This is free documentation; you can redistribute it and/or +.\" modify it under the terms of the GNU General Public License as +.\" published by the Free Software Foundation; either version 2 of +.\" the License, or (at your option) any later version. +.\" +.\" The GNU General Public License's references to "object code" +.\" and "executables" are to be interpreted as the output of any +.\" document formatting or typesetting system, including +.\" intermediate and printed output. +.\" +.\" This manual is distributed in the hope that it will be useful, +.\" but WITHOUT ANY WARRANTY; without even the implied warranty of +.\" MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the +.\" GNU General Public License for more details. +.\" +.\" You should have received a copy of the GNU General Public +.\" License along with this manual; if not, write to the Free +.\" Software Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, +.\" USA. +.\" +.\" Minor polishing, aeb +.\" Modified, 2002-06-16, Mike Coleman +.\" +.TH HOSTS 5 2002-06-16 "Debian" "Linux Programmer's Manual" +.SH NAME +hosts \- The static table lookup for host names +.SH SYNOPSIS +.B /etc/hosts +.SH DESCRIPTION +This manual page describes the format of the +.I /etc/hosts +file. This file is a simple text file that associates IP addresses +with hostnames, one line per IP address. For each host a single +line should be present with the following information: +.RS +.PP +IP_address canonical_hostname aliases +.RE +.PP +Fields of the entry are separated by any number of blanks and/or +tab characters. Text from a "#" character until the end of the line is +a comment, and is ignored. Host names may contain only alphanumeric +characters, minus signs ("-"), and periods ("."). They must begin with an +alphabetic character and end with an alphanumeric character. +Aliases provide for name changes, alternate spellings, +shorter hostnames, or generic hostnames (for example, +.IR localhost ). +The format of the host table is described in RFC 952. +.PP +The Berkeley Internet Name Domain (BIND) Server implements the +Internet name server for UNIX systems. It augments or replaces the +.I /etc/hosts +file or host name lookup, and frees a host from relying on +.I /etc/hosts +being up to date and complete. +.PP +In modern systems, even though the host table has been superseded by +DNS, it is still widely used for: +.TP +.B bootstrapping +Most systems have a small host table containing the name and address +information for important hosts on the local network. This is useful +when DNS is not running, for example during system bootup. +.TP +.B NIS +Sites that use NIS use the host table as input to the NIS host +database. Even though NIS can be used with DNS, most NIS sites still +use the host table with an entry for all local hosts as a backup. +.TP +.B isolated nodes +Very small sites that are isolated from the network use the host table +instead of DNS. If the local information rarely changes, and the +network is not connected to the Internet, DNS offers little +advantage. +.SH EXAMPLE +.nf + 127.0.0.1 localhost + 192.168.1.10 foo.mydomain.org foo + 192.168.1.13 bar.mydomain.org bar + 216.234.231.5 master.debian.org master + 205.230.163.103 www.opensource.org +.fi +.SH "HISTORICAL NOTE" +Before the advent of DNS, the host table was the only way of resolving +hostnames on the fledgling Internet. Indeed, this file could be +created from the official host data base maintained at the Network +Information Control Center (NIC), though local changes were often +required to bring it up to date regarding unofficial aliases and/or +unknown hosts. The NIC no longer maintains the hosts.txt files, +though looking around at the time of writing (circa 2000), there are +historical hosts.txt files on the WWW. I just found three, from 92, +94, and 95. +.SH FILES +.I /etc/hosts +.SH "SEE ALSO" +.BR hostname (1), +.BR resolver (3), +.BR resolver (5), +.BR hostname (7), +.BR named (8), +Internet RFC 952 +.SH AUTHOR +This manual page was written by Manoj Srivastava <srivasta@debian.org>, +for the Debian GNU/Linux system. |