request.http.header.X-Forwarded-For = nul

[Suresh Kumar Gubbala]

Hi Guys,

I am trying to capture the publicIP using request.http.header.X-Forwarded-For for a SOAP/WSDL API onboarded.
But I am unable to capture it always null.
Though I could get tcp.remoteIP.
What might be the blocker?

Thanks,
Harsha

[Zhijun He]

Dear Harsha,
If gateway is behind a load balancer, the tcp.remoteIP will be always the IP of load balancer.
The x-forwarded-for header a de-facto standard header for identifying the originating IP address of a client connecting to a web server through an HTTP proxy or a load balancer. 
Your load balancer needs to be configured to store the original IP to the x-forwarded-for header before forward the request to gateway.
Check with your network team on that.

Regards,
Mark

[Chris Bertagnolli]

A load balancer does not guarantee that ${request.tcp.remoteIP} will be load balancer - depends on setup. That should only be true if they perhaps terminate SSL before passing request along since that's only way they'd be able to inject the X-Forwarded-For header.

If the load balancer is just a passthrough though then the X-Forwarded-For header shouldn't be present. In that situation then ${request.tcp.remoteIP} should work - works for all of our load balanced systems without any issues.

Not knowing their setup, this is just a generic statement that request.tcp.remoteIP can work even in load balanced setups :). If they are in fact terminating SSL then of course it'd be on the LB to make sure it's inserting the appropriate HTTP header.