Before you can start the TN3270 mainframe display specified in the IDE options, ensure that your project is associated with an enterprise server and that the server is running.
When you start debugging, the IDE automatically launches the TN3270 Mainframe Display specified in the IDE preferences and connects it to the enterprise server on which your application is running.
If the TN3270 Mainframe display of choice is closed, you can open it in one of the following ways:
Alternatively, you can show the Rumba+ Desktop Mainframe Display view as follows:
The view automatically connects to the enterprise server on which the application you are debugging runs.