how can i get machine ip

You cant, at least not that I have seen. Nor have I ever found a good reason to gather that info... it provides inconsistent and overlapping data, but it is not my project/code. Do as you please... I am only going to suggest you really think about your "End Goal" and possibly find a better solution (post your reason... I am curious as to why you want local IP's)

Check the global variable: $_SERVER['REMOTE_ADDR']

@cmdobueno I just want to track how many user visit my website in a day if 100 user in same lan i will get only one user as unique ip if i use $_SERVER['REMOTE_ADDR']

Correct, tracking in that way is generally extremely hard.

Generally speaking, tracking like that is hard in general. Sometimes it is best to generate a token for the browser, which I will not go into details on (I personally have no done that... so I cant help with how to do it)... I just know there is a way to create a "finger" print with the browser... it is not perfect, and you can easily "trick" the system into allowing the total views/visitors to go up... but that is life...

Just use google analytics or something. They do it better than you can anyway.

Amen to that. Trying to track unique visitors is not as simple as people make it out to be...