Old ROS2 topics are not visible from a newly connected device

I have a setup with husarnet, ros2 iron, ros2router and fastrtps as here: GitHub - DominikN/ros2router-service-test

I confirm that everything communicates and works as expected initially. However, if I disconnect listener and reconnect listener to the vpn after a day for example, I cannot see any of the topics that are still running on the talker. If I start new topics (e.g. start a new demo_nodes_cpp talker) I will be able to see them on the listener.

I confirm that all the docker containers are up on the talker and have tried restarting the ros2router and the husarnet containers on the talker, but that did not help.

What can I do to see ros2 topics that have been running for a while on one machine connected to a husarnet vpn from another machine newly connected to the same husarnet vpn?

From my experience, I have seen similar issues when I use any ROS2 release except for Humble.

For example, in Foxy I have observed that whilst using Husarnet if I run inside a terminal

ros2 run demo_nodes_cpp talker

and then do (on the same machine)

ros2 topic list

I do not see the chatter topic.

However, if I do not export the .xml that husarnet-dds singleshot provides in both the terminals. Regular ROS2 behaviour is retained.

I would try migrating to Humble since it has LTS support.