Upgrading a slink r1 CD to a slink r4 CD

[Jean-Baptiste Marchand <jbm@alternative-advice.com>]

Hi everyone,

I have the two i386 binaries CD's of Slink r1 and I would like to
upgrade it to two i386 binaries CD's of Slink r4.

I believe that with rsync, it is possible to upgrade ISO images, by
downloading only the differences between the images but I'm not sure.

Apart from the fact that the Slink r4 are not done yet, I would like
to test this with Slink r3.

My questions are:

- How can I obtain an iso image of my Slink r1 Cd's ? 
  I've done a dd like : 
        $ dd if=/dev/hda of=slink1_image.iso 
  but I'm not sure it is okay.
  Or should I copy the whole cd's and make the images with mkisofs ?

- Is it really possible to obtain a Slink release x (with x > 1) with
  iso images of Slink release 1, without downloading the whole new
  images ?

Thank you for your help :)

Jean-Baptiste Marchand
-- 
Jean-Baptiste.Marchand@epita.fr
GNU Emacs : Eventually Malloc's All Computer Storage
(From the Jargon File : www.tuxedo.org/~esr/jargon/)