For my project I have the following setup:

• docker container running ros2 humble node ( for example demonodescpp talker)
• docker container running ros2 galactic node (for example demonodescpp listener)

both container started with privileged mode and network-mode host. they also have same environment variables:

export ROS_DOMAIN_ID = 5
export RMW_IMPLEMENTATION=rmw_fastrtps_cpp ( not sure, really needed)

Problem: The listener node does not receive any messages from talker node.

Question: Do I miss something? Any suggestion would helpful Thanks