[lug] ifupdown mapping

[J. Wayde Allen]

OK, I'm setting up a new Debian laptop and have been trying to create
mappings for multiple network configurations.  According to the man pages
for ifupdown I should be able to setup the /etc/network/interfaces file to
read something like:

  # The loopback interface
  auto lo
  iface lo inet loopback

  mapping eth0
     script /usr/local/somescript
     map home eth0-home
     map work eth0-work

  iface eth0-home inet static
     address xxx.xxx.xxx.xxx
     netmask xxx.xxx.xxx.xxx

  iface eth0-work inet static
     address yyy.yyy.yyy.yyy
     netmask yyy.yyy.yyy.yyy

What I can't seem to get my head around is the mapping script.  What
exactly does this do?  I guess it seems to me that the "map name" lines
should point to the appropriate interface definition.  Can someone clarify
this for me?

- Wayde
  (wallen at its.bldrdoc.gov)

      --------------------------------------------------------
                            ISART 2004
       International Symposium on Advanced Radio Technologies
         http://www.its.bldrdoc.gov/meetings/art/index.php
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