The "*Connection to ec2-34-195-32-161.compute-1.amazonaws.com:5432 refused*" error would have occurred when the Virtual DataPort server is unable to reach the PostgreSQL in the EC2 instance. In order to resolve the issue, I would perform the following checks:
* Check whether the server you’re connected to has started and running.
* Check if you have a firewall that is blocking the port that you are trying to listen to.
Additionally, in order to get more information about this error, I would check the **vdp.log** file which is located under the folder “**<DENODO_HOME>/logs**”
Hope this helps!