After the Xen presentation at the FOSDEM, I did want to test this wonderful concept. I google around and found a very good page: http://julien.danjou.info/xen.html. I did not read all the document and install and start configuring everything. The first problem was network. It was hard to know exactly what was wrong because the machine is on a NAT, behind a firewall and it's a friend/co-worker who manage it and he really block everything! :-)
I went to OTFC#debian-xen trying to find some help and chatted with 'jd_'... the author of the link above. Some of the best mistake where not configuring /etc/fstab, bad MAC Address, and change the tty1 entry with 'console' in /etc/inittab. Julien also gave me another very good documentation in french: http://wiki.gcu.info/doku.php?id=linux:xen.
The Xen experience is smashing! You have two independant Debian system (with two different IP's) on the same box! Maybe the experienced admins will laugh reading these lines, but I'm very impressed by my Xen experience.
Julien also invited me for a dinner on a wendsday evening because he said "I'm a winner" :-D.
Many thanks Julien.