The link describes all the outputs and inputs to the robot.
https://www.universal-robots.com/articles/ur/real-time-data-exchange-rtde-guide/
https://s3-eu-west-1.amazonaws.com/ur-support-site/53318/scriptManual.pdf
The link is for non-linux platforms, but can be changed for linux platforms if required.
https://www.universal-robots.com/download/?option=77063#section41570
Follow the last section of the link (Part 8: Set Up of Network Adapter)
https://academy.universal-robots.com/media/jiehhszc/ursim_vmoracle_installation_guidev03_en.pdf
If you cannot ping from the VM to the host machine, then try checking out the following link: https://superuser.com/questions/1214547/unable-to-ping-from-vms-to-host-machine
Follow the instructions in the link: https://pypi.org/project/urinterface/
Start the virtual machine, and start the program URSim UR5. Clikc on the Power off button in the left corner. A new screen will be shown, with an On button in the middle. Click the On button, then clikc the Start button. The virtual robot should now be on. The status of the robot is shown in the left bottom corner, where the status should now be Normal. Run the file run_experiment.py in the folder robot_sim_tests and remember to specify the correct IP address of the virtual machine.
You can confirm if the robot starts running, when you run the python experiment by looking at the bottom left corner of the simulator. The figure below shows how the simulator looks when it is running.
You can also change the specified IP address of the VM and it should give an error, explaining it cannot make a connection.