[lug] ifupdown mapping

[J. Wayde Allen]

On Thu, 16 Oct 2003, Toni Janz wrote:

> I think an easy solution in your case might be this:
> 
> http://packages.debian.org/stable/admin/laptop-net.html

I have the packages intalled, my question has more to do with "how" this
works.  Let's see, I may have not been sufficiently clear with my initial
question.

Let's say we have the following in the /etc/network/interfaces file:

>   mapping eth0
>      script /usr/local/somescript
>      map home eth0-home
> 
>   iface eth0-home inet static
>      address xxx.xxx.xxx.xxx
>      netmask xxx.xxx.xxx.xxx

It seems to me that the mapping stanza provides the logic necessary to
map either "home" or "eth0-home" to the eth0 interface.  My thought was
that simply making the call 

   /sbin/ifup eth0-home

or 

   /sbin/ifup home

should be able to configure the appropriate interface.  However, this
doesn't appear to be the case and the documentation indicates that the
mapping script specified by the line

>      script /usr/local/somescript

has to run for anythinng to happen.  As far as I can tell, this script
only needs to return the value of "eth0-home" in order to choose the
configuration information specified in the section.

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

Evidently the "map" lines only supply arguments to the script?

- Wayde
  (wallen at village.org)