I have a hosted Exchange server on Rackspace. I am using it to test Exchange Web Services integrated with my personal web application. Rackspace provides an Autodiscovery URL through which EWS connections can be made.
I can connect just fine locally. However, when I try to test the same functionality on my staging servers (which are Amazon ec2 instances), I do NOT get an API response. In fact, the httpd thread serving the end user just hangs indefinitely, which means the user is not able to load ANY other pages in my app, even after the timeout interval.
I have checked the error/access logs for apache, php, and even my load balancer's access logs. None of these resources provided any insight to the problem.
As I said, I have no problem connecting to the exchange server from my local copy of my web app. Why would this be the case? What do I need to do to fix connectivity on my staging servers?