2 domain run with same content

How I can use my another domain mysite.net to point to my main domain mysite.com.2 domain run with same content.
Can you help in this regard?

Ex: DragonByte Technologies - Premium vBulletin Modifications and DragonByte Technologies - Premium vBulletin Modifications

Hello
I Didn't Understand,What is happening with mysite.com?Still my website does not working India on some locations,And now our some member Reported site not work in Bangladesh,When go my site link Show this error message ("This website/URL has been blocked until further notice either pursuant to Court orders or on the Directions issued by the Department of Telecommunications")It's working fine with a proxy.Have any solution for Unblock my site?If I change my site IP address,Can i get fixed this issue?
Thanks