iis - .Net Core 5 API keeps returning the same IP

Question

In my .net core 5 api I need to get the remote IP from request. It works fine on my test server. Checked it several times from different networks.

BUT

on my client's server, I'm getting the same IP address regardless from where I'm calling the API. So, my problem is that on my server everything works fine, but on client's server, I'm getting false IP address.

I've installed the .Net 5 SDK I've compared it to my server and IIS (different versions of IIS, but configuration seems fine)

Any ideas?

question from:https://stackoverflow.com/questions/66054940/net-core-5-api-keeps-returning-the-same-ip

Answer 1

I will assume that you have LB environment. SO most probably you getting the LB IP. If this is the case. you should configure the LB to allow HTTP header transfer to the internal requests. Especially if you use internal HTTP direction across the DMZ. mainly you can rely on "x-forwarded-for" and the proxy server (LB) will fill that in and pass it to your internal servers.