1. Is it mandatory to connect the Forti to internet in order to registrate the license? I saw the Forticare turning around searching something.
-> Yes, you must have it on the Internet unless you have a FortiManger setup. https://help.fortinet.com/fos50hlp/56/Content/FortiOS/fortigate-system-administration/Central%20Management/fortigate-licensing-isolated/Licensing_Config_FGT_No_Connectivity_Access_Local_FMG_as_FDN.htm2. Same question for firmware updates, need internet connection? Is there a method to do offline?You can download the files then apply them
3. There is a case 'Enter registration code' on FortiGuard license information, where can I get this code?
When you register the firewall you can use the serial number instead of a registration code. If you bought advanced features you get a PDF file with the code.