Is it legal to rent a house from someone and sublease it to other people?

Like. Do I even have to live in the house? I want to rent a house that is underpriced say... $600 and rent out the 3 bedrooms for $350 each. That way I collect $1050 and pocket $450. I'll probably pay for the utilities and pocket about $200. Yes, I did find a house for $600 with 3 bedrooms and 2 bathrooms. Is there anything illegal with doing this? I mean... Of course I'll get the owner to sign a paper saying that I am allowed to sublease. But the owner wont know im sublease all the bedrooms and i'm not even staying there. What are your thoughts on this. Good idea? Bad idea? P.S. If im not even living there but paying the $600 rent, does the owner have to give me 30 days to "move out"?