How to - I want change localhost:8080 to mysystemname:8080

How to - I want change localhost:8080 to mysystemname:8080

Hi, 

I have installed ServiceDeskplus on my system for learning purpose. i want to change URL from https://localhost:8080 to https://<<mysystem's Hostname>>:8080

I tried to change the same in Admin->General->Advanced Portal Settings -> "Configure alias URL accessible to the internet". But its not opening. even at above setting, i clicked on "Check alias URL", but that too giving error.

Error is: "connect failed". I am new to this tool. please help.

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