Langue: en

Version: dnsutl (mandriva - 01/05/08)

Section: 1 (Commandes utilisateur)


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


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


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.


The following options are understood:

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

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

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

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.


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.


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
         ether   a       2:7:1:f:b7:fb
         in      hinfo   "IBM-PC 486" "MSDOS"
 venus   in      a
         ether   a       2:60:8c:2d:20:c4
         in      hinfo   "IBM-6000/590" "UNIX AIX 3.2.5"
 earth   in      a
         ether   a       08:00:20:79:1f:0d
         in      hinfo   "Sun-4/5 (SPARCstation 5)" "UNIX SunOS 5.4"
 mars    in      a
         ether   a       aa:0:4:0:86:53
         in      hinfo   "DEC-Alpha 3000" "UNIX OSF/1 V3.2"
 jupiter in      a
         ether   a       8:0:2b:99:49:ad
         in      hinfo   "DEC-VXT2000+ XTerminal" "Other: X11R5"
         bootp   tc      dec-vxt-2000
 saturn  in      a
         ether   a       0:40:10:56:43:57
         in      hinfo   "Apple-Macintosh IIsi" "MacOS 7.5.3"
 neptune in      a
         ether   a       0:aa:0:69:7c:5b
         in      hinfo   "IBM-PC" "MSDOS"
 uranus  in      a
         ether   a       0:0:e8:a4:0:25
         in      hinfo   "IBM-PC" "MSDOS"
 pluto   in      a
         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.


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.

dns-ethers version 1.8,
Copyright (C) 1990, 1991, 1992, 1993, 1994, 1995, 1996, 1999, 2000, 2001, 2003, 2004, 2005, 2006 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.


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