In productionProadvancedQoS durability
The late subscriber never learns its config
Let a config client that joins after the one-shot /robot_config publish still receive the latched sample, without changing the publisher.
Pairs with Parameters and launch in ROS 2 Systems Debugging. Read the concept first, then diagnose it here.
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/robot_config appears in `ros2 topic list`, but the client's /config_status stays 'PENDING' forever because it started after the single latched publish.
Ubuntu 24.04, ROS 2 Jazzy, Python and C++ nodes, browser telemetry workspace
System boundary
Trace only the relevant path.
config_broadcaster/robot_configconfig_client
How this lab works
You diagnose it — no command list.
Open the repair workspace and gather your own evidence in a real terminal. No diagnostic commands are handed to you — finding the fault is the exercise. Stuck? Progressive hints unlock inside the workspace.
Verification
Your repair must pass more than the visible symptom.
- Client publishes /config_status
- Late-joining client receives the latched /robot_config
- Hidden regression behavior
- Root cause explanation