Errors when Setting Up a Reverse Proxy

Situation: We were trying to set up a reverse proxy on IHS (IBM HTTP Server) for a back-end website we did not host

Problem1: After the setup was complete we received this error when trying to reach the web site:

Proxy Error

The proxy server received an invalid response from an upstream server.

The proxy server could not handle the request GET /.

….

Also, the IHS error log reported this error:

[error] [client xxx.xxx.xxx.xxx] proxy: DNS lookup failure for: http://www.backend.website.com returned by /

Solution: Our web server could not resolve the URL of the back-end website. We needed to add a hosts file entry on our server to resolve the issue.

Problem 2: After fixing the above problem we received a 500 HTTP response in the browser and the following in the IHS error log:

[error] SSL0266E: Handshake Failed, Could not establish SSL proxy connection.

Solution: It turned out that the back-end website was using a self-signed certificate. We had to download and add that certificate to the IHS trust store.