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Nodes missing from `ros2 node list` after relaunch

See original GitHub issue

Bug report

Required Info:

Operating System:
- Ubuntu 20.04
Installation type:
- Foxy binaries
Version or commit hash:
- ros-foxy-navigation2 0.4.5-1focal.20201210.084248
DDS implementation:
- Fast-RTPS (default)
Client library (if applicable):
- n/a

Steps to reproduce issue

1

From the workspace root, launch (e.g.) a TurtleBot3 simulation:

export TURTLEBOT3_MODEL=burger
export GAZEBO_MODEL_PATH=$GAZEBO_MODEL_PATH:$(pwd)/src/turtlebot3/turtlebot3_simulations/turtlebot3_gazebo/models
ros2 launch turtlebot3_gazebo turtlebot3_world.launch.py

Then, in a second terminal, launch the navigation:

export TURTLEBOT3_MODEL=burger
ros2 launch turtlebot3_navigation2 navigation2.launch.py use_sim_time:=true

Print the node list:

ros2 node list

Close (ctrl-c) the navigation and the simulation.

2

Relaunch from the same respective terminals, the simulation:

ros2 launch turtlebot3_gazebo turtlebot3_world.launch.py

and the navigation:

ros2 launch turtlebot3_navigation2 navigation2.launch.py use_sim_time:=true

Print the node list again (2nd time):

ros2 node list

Close (ctrl-c) the navigation and the simulation. Stop the ros2 daemon:

ros2 daemon stop

3

Relaunch from the same respective terminals, the simulation:

ros2 launch turtlebot3_gazebo turtlebot3_world.launch.py

and the navigation:

ros2 launch turtlebot3_navigation2 navigation2.launch.py use_sim_time:=true

Print the node list again (3rd time):

ros2 node list

Expected behavior

The node list should be the same all three times (up to some hash in the /transform_listener_impl_... nodes).

Actual behavior

The second time, the following nodes are missing (the remainder is practically the same):

/controller_server
/controller_server_rclcpp_node
/global_costmap/global_costmap
/global_costmap/global_costmap_rclcpp_node
/global_costmap_client
/local_costmap/local_costmap
/local_costmap/local_costmap_rclcpp_node
/local_costmap_client
/planner_server
/planner_server_rclcpp_node

The third time, after stopping the daemon, it works as expected again.

Note, that everything else works fine and in case of the above navigation use case, the nodes are fully functional.