Hi Mouad,
If your goal is having two seperate 11sp15 databases, I would recommend just adding an additional <DB-Connection> tag within your innovatorserverconfig.xml file, which can be located in the root of your aras installation. This will allow you to log into both databases from a your "innovatorServerOne" url.
If you'd like to have two separate instances, you'll have to modify the GUID of the installer process to load an additional instance to your machine. Subscribers have access to the CD image which contains a changeGUID.exe file within the utilities folder. Dragging the installer on top of this executable will change the GUID of its installer, allowing for a parallel download. Just ensure that when you're running through the installer that you're giving everything unique names.
AJ
