How to get a user's client IP address in ASP.NET?

Question

We have Request.UserHostAddress to get the IP address in ASP.NET, but this is usually the user\'s ISP\'s IP address, not exactly the user\'s machine IP address

Answer 1

I think I should share my experience with you all. Well I see in some situations REMOTE_ADDR will NOT get you what you are looking for. For instance, if you have a Load Balancer behind the scene and if you are trying to get the Client's IP then you will be in trouble. I checked it with my IP masking software plus I also checked with my colleagues being in different continents. So here is my solution.

When I want to know the IP of a client, I try to pick every possible evidence so I could determine if they are unique:

Here I found another sever-var that could help you all if you want to get exact IP of the client side. so I am using : HTTP_X_CLUSTER_CLIENT_IP

HTTP_X_CLUSTER_CLIENT_IP always gets you the exact IP of the client. In any case if its not giving you the value, you should then look for HTTP_X_FORWARDED_FOR as it is the second best candidate to get you the client IP and then the REMOTE_ADDR var which may or may not return you the IP but to me having all these three is what I find the best thing to monitor them.

I hope this helps some guys.