F5 Big-IP, X-Forwarded-For and IIS Logs

Question

I've got an F5 Big-IP that is mangaged by our hosting provider. It's dedicated to our private VLAN, etc. Works great :)

We requested them to add in an X-Forwarded-For HTTP-Header field. They've done that and we can now access that in the code. Awesome :)

But .. for our IIS logs, it's still the IP of the F5 machine. I think I was told that we need to apply an ISAPI filter (cringe!) to the IIS server(s).

1. Can someone confirm this?
2. If #1 == yes, is there a file/instructions how to do this for our IIS7 web servers on windows 2008 machines.

cheers :)

Answer 1

I published an ISAPI filter to work with our BIG-IP's and have just updated it with full x86 and x64 support. Check out the blog post I wrote on it a while ago. Just copy the enclosed F5XForwardedFor.dll to your server and reference it in the ISAPI section of your virtual site.

http://devcentral.f5.com/weblogs/joe/archive/2005/09/23/1492.aspx

-Joe

Answer 2

This is discussed in this thread of the IIS Microsoft Community. It seems there is a helper to do that for IIS (Especifically stated to work with Microsoft ARR but it should work for any reverse proxy or load balancer).