If you want to install your SAP system with VIRTUAL HOSTNAME then you should use the following SAPINST Switch to do it…

To install SAP using virtual hostname , navigate to the directory where the sapinst tool is present (or SWPM DVD)

Then you should use the SAPINST command with following switch on Command Prompt

sapinst SAPINST_USE_HOSTNAME=VirtualHostName

All SAP Installation steps will use this “Virtual Hostname” for this installation.