One of the ways to get a clear picture about a communication between two servers is to use WireShark tool. I have to admit that this tool has much functionalities that I don’t know anyone that know how to use all of them J but everyone agree that it is the best networking troubleshooting tool that you can find right now (and it is free).
As I explained in a past post you can create a simple and useful report about the number of connections executed in a testing using WireShark and Excel and clicking just in two options of the tool http://watchingthecloud.blogspot.com.es/2010/06/how-to-see-connections-in-wireshark.html
You can filter the log using simple commands like: DTC, HTTP, or ip.addr==10.10.10.10
If you need to demonstrate that the communication between your server and other one has been executed successfully, you can use the ip.addr filter to catch just the packets related to the destination server (ip.addr will filter all the packets from or to IP address specified). Then, go to Statistics menu and select Flow Graph…
Leave the default values and click OK button. A graph analysis will be created. You can use it to shown if a communication or interface has been executed correctly or not:
Angel Perez Palacios 