I am trying to listen to a topic published by my robot on my host machine.
My setup is as follows:
Robot: ROS2 Foxy on Ubuntu 20.04
Host: ROS2 Galactic on Ubuntu 20.04
Both the host and the robot are connected to an OpenVPN server and I can ping/ssh from any one of them to the other when OpenVPN is running.
The VPN uses tun0 interface on both the robot and the host and the IP addresses of the host machine and the robot are 10.8.70.4 and 10.8.70.6 respectively.
My problem is that published topics on any of the machines don’t get discovered by the other machine.
Do I have to set the DDS network interface on both FastDDS and CyclonDDS sides to use tun0? Or do they publish on all interfaces by default? If so, how shall I do that?
Is the issue related to OpenVPN? Do I need to modify the default OpenVPN server communication so that my nodes can discover each other over the VPN?