However, you won't be entitle for support, if you have issue or question, this QlikSense discussion board would help you for the free edition of QlikSense issue or concerns. Now, for the Server piece, you must buy a license and your account manager can assist you with that.
Giuseppe Novello Principal Technical Support Engineer @ Qlik
I will try to clarify a little more: QlikSense Desktop is free. QlikSense Server has to be licensed. If you obtain a QlikSense Server license, you are also entitled for support for your Desktop solution.
"Accordingly to your reply to first point, So I do not think we would have any additional hardware requirement in case we need to go for Qlik Sense."
You cannot run QlikSense Server and QlikView Server parallel on the same machine. An "upgrade" as of such is not possible, but more so you will need to migrate to the different product. Additional hardware may be required to facilitate this.
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