Hello I'm new in this forum, so i would like that you forgive me for my blissfully and my low English level. I'm a trainee in company one month ago, and my mission is to migrate 3 physicals servers to a virtualization technology. The company edit softwares for E-learning so there are lots of data like videos, flash and compressed (zip). This is some inventory of the servers: OS: Debian, 2 redhat, apache, php/mysql, sendMail/Dovecot, webmin with virtualmin template to create dynamically the web sites because there is no sysadmin ... The future provider will be responsible of to secure, update and create the virtual machines (outsourcing) and with a RedHat OS's. So i want that you help me to choose a virtualisation technologie (for the i prefer KVM of Redhat RHEV, VMWare is expensive), how evaluate the hardware needs (this for evolution of 4 or 5 years) and to elaborate a good planing to don't forget any think. Thank you for your responses.