Hi all. At the moment i use one ms sbs server 2k3 std as domain controller with ms exchange as file and print server. this server has its own hardware. A second ms server 2k3 std runs in vmware server vm at separate hardware. Furthermore at this vmware server a linux system installed as mail gateway with spam- and virus protection even runs as vm. In a few months another MS SQL Server with ERP System will be installed. It is a small environment with about 15 users until now. I think it will be in the next few years not more than 25 users. I would like to get all the server together at one server hardware. MS sbs server 2k3 std will be migrate to MS sbs 2011 server premium. After migration, it should look like this: XEN-Server (dom0) | - (domU1) MS sbs 2k11 as domain controller and MS exchange server, file- and print server | - (domU2) MS sql server with ERP system | - (domU3) MS server 2k3 std for acad | - (domU4) debian squeeze as mail gateway, spam- and virus protection | - (domU5) reserve for future system My question: which is the best hardware plattform to install xen and all server mentioned above? Is it advisable to install MS SQL server under xen as vm or is it better to run MS SQL server on its own hardware? thanks stefan