dns-ethers(1)

NAME
dns-ethers - generate /etc/ethers entries from DNS tables

SYNOPSIS
dns-ethers [ option... ][ infile [ outfile ]]
dns-ethers -Help
dns-ethers -VERSion

DESCRIPTION
The dns-ethers program is used to generate the /etc/ethers entries from DNS tables.

If the input file is not named, or the name '-' is used, the standard input is read.

If the output file is not named, or the name '-' is used, the startdard output is written.

A fake DNS type of ``ether'' is used, instead of the usual ``in'' type, to enable the use of the ``a'' to store the addresses.

OPTIONS
The following options are understood:

-Verbose
    This option may be used to see what dns-ethers deciphers each resource record as.

-Help
    This option may be used to get more information about how to used th dns-ethers program.

-VERSion
    This option may be used to see what version of the dns-ethers program is running.

-Idirectory
    This option may be used to set the search path for include files.

All other options will produce a diagnostic error. Options may be abbreviated, the minimum abbreviation is shown in upper-case. Options are case insensitive. Options and file names may be mixed arbitrarily on the command line.

EXIT STATUS
The dns-ethers command will exit with a status of 1 on any error. The dns-ethers command will only exit with a status of 0 if there are no errors.

EXAMPLE
The idea is that you have all of the information concerning each computer in the one file. This makes it less likely that something will be omitted, and simpler to change if the name or IP address changes.

Given a database file called ``example.com'' and which contains the following text
    $origin example.com.
    @	in	soa	exmaple.com. hostmaster.example.com. (
    			990101001	; serial
    			10800		; refresh: 3 hours
    			1800		; retry: 30 minutes
    			3600000		; expire: 1000 hours
    			86400 )		; minimum: 24 hours
    mercury	in	a	182.168.1.1
    	ether	a	2:7:1:f:b7:fb
    	in	hinfo	"IBM-PC 486" "MSDOS"
    venus	in	a	182.168.1.2
    	ether	a	2:60:8c:2d:20:c4
    	in	hinfo	"IBM-6000/590" "UNIX AIX 3.2.5"
    earth	in	a	182.168.1.3
    	ether	a	08:00:20:79:1f:0d
    	in	hinfo	"Sun-4/5 (SPARCstation 5)" "UNIX SunOS 5.4"
    mars	in	a	182.168.1.4
    	ether	a	aa:0:4:0:86:53
    	in	hinfo	"DEC-Alpha 3000" "UNIX OSF/1 V3.2"
    jupiter	in	a	182.168.1.5
    	ether	a	8:0:2b:99:49:ad
    	in	hinfo	"DEC-VXT2000+ XTerminal" "Other: X11R5"
    	bootp	tc	dec-vxt-2000
    saturn	in	a	182.168.1.6
    	ether	a	0:40:10:56:43:57
    	in	hinfo	"Apple-Macintosh IIsi" "MacOS 7.5.3"
    neptune	in	a	182.168.1.7
    	ether	a	0:aa:0:69:7c:5b
    	in	hinfo	"IBM-PC" "MSDOS"
    uranus	in	a	182.168.1.8
    	ether	a	0:0:e8:a4:0:25
    	in	hinfo	"IBM-PC" "MSDOS"
    pluto	in	a	182.168.1.9
    	ether	a	8:0:9:d:2a:87
    	in	hinfo	"HP-Laser-Jet 4" "None"
    lp	in	cname	pluto
You can generate the /etc/ethers file using the following command
    % dns-ethers example.com /etc/ethers
    %
Here is what you would see as the output
    2:7:1:f:b7:fb	mercury
    2:60:8c:2d:20:c4	venus
    8:0:20:79:1f:d	earth
    aa:0:4:0:86:53	mars
    8:0:2b:99:49:ad	jupiter
    0:40:10:56:43:57	saturn
    0:aa:0:69:7c:5b	neptune
    0:0:e8:a4:0:25	uranus
    8:0:9:d:2a:87	pluto
Note that the output uses relative names.

  Makefile
All of this can be automated using the following makefile fragment:
    /etc/ethers: example.com
    	dns-ethers example.com $@
By doing this, all you need to do is edit the example.com file, and the use the make(1) command to bring everything up-to-date.

If you were using NIS, NIS+ or LDAP you would update them, rather than the static file.

COPYRIGHT
dns-ethers version 1.6,
Copyright (C) 1990, 1991, 1992, 1993, 1994, 1995, 1996, 1999, 2000 Peter Miller; All rights reserved.

The dns-ethers program comes with ABSOLUTELY NO WARRANTY; for details use the 'dns-ethers -VERSion Warranty' command. The dns-ethers program is free software, and you are welcome to redistribute it under certain conditions; for details use the 'dns-ethers -VERSion Redistribution' command.

AUTHOR
Peter Miller | E-Mail: | millerp@canb.auug.org.au
/\/\* | Web: | http://www.canb.auug.org.au/~millerp/