Howto upgrade from Debian 4 (Etch) to Debian 5 (Lenny)
 

You probably noticed by now, that Debian GNU/Linux 5.0 aka "Lenny" hasn't been released in September. The reason: too many bugs need to be fixed.

When Lenny has been released, you can upgrade from Etch to Lenny according the steps below:
(According the official Debian documentation, these 5 steps describe the safest way to do that job).

STEP 1:
-------
Make a backup of your current Debian Etch system.

STEP 2:
-------
Change the content of the file /etc/apt/sources.list.
This means that you need to change "etch" into "lenny".
So in my case i have to change:

deb http://ftp.nl.debian.org/debian/ etch main
deb-src http://ftp.nl.debian.org/debian/ etch main

deb http://security.debian.org/ etch/updates main contrib
deb-src http://security.debian.org/ etch/updates main contrib

into:

deb http://ftp.nl.debian.org/debian/ lenny main
deb-src http://ftp.nl.debian.org/debian/ lenny main

deb http://security.debian.org/ lenny/updates main contrib
deb-src http://security.debian.org/ lenny/updates main contrib


Beware:
if you use "stable" instead of "etch", your system will make use of the packages provided by Debian Lenny from the moment on that Lenny gets stable!

STEP 3:
-------
Execute the command: aptitude update
to get information about new packages

STEP 4:
-------
Execute the command: aptitude install dpkg aptitude apt
to install the newest package management

STEP 5:
-------
Execute the command: aptitude full-upgrade

Reference:
The Debian Devel anounce

Confirmation
 

I tested this method on my testing server with Debian Etch and ISPConfig 3.0.0.7.
The upgrade to Debian Lenny was succesful. :)
Don't perform this upgrade on a production server until Lenny is stable.
It seams that ISPConfig 3 runs fine on Lenny.

Hans, how do I make sure I update etch instead of stable?

Never mind, I found it:

/etc/apt/sources.list should have (or another server if you're not near Essen)

----------------------

deb http://debian.uni-essen.de/debian/ etch main non-free contrib

deb http://security.debian.org/ etch/updates main contrib non-free

----------------------

Actually, when Lenny goes stable, it would be a good idea to put a "heads up" notice in the forums before noobs like me destroy their servers ;-)