Unable to launch robot server within docker container.

[szhaovas]

Hello developers, thank you for maintaining robo-gym!

I have been having troubles running robo-gym inside a docker container. My goal is to run the robo-gym server side from within the container, and run the robo-gym training script on my host machine. However, I cannot seem to launch robot server inside the container, and the application always stalls on the step Starting Robot Server....

I initially thought it to be a docker port problem, but even if I launched both the server and the training script within the same docker container, I still could not launch the server, as shown (test.py in the right pane is simply the Random Agent MiR100 Simulation Environment example in README):

Steps to reproduce

• I have pushed my docker image to dockerhub docker pull szhaovas/robogym_test.
  • This image was built from noetic.Dockerfile at my fork of the robo-gym-robot-servers repo. This dockerfile is similar to your original, except it also installs robo-gym for running the training script.
• Launch a container with docker run --rm -it szhaovas/robogym_test.
• Within the container terminal, run start-server-manager && attach-to-server-manager.
• Right click to split the tmux pane, and on the other pane, run python3 test.py.

My setup

• Probably doesn't matter, but my host machine is a MacBook Air M2 2023, and its OS is Ventura 13.5.2.
• My docker version is 26.1.1.

Additional info

• I think the problem is specific with docker only, since I was able to run the same example in a Ubuntu 20.04 ROS Noetic virtual machine.
• The line that doesn't return seems to be the self.tmux_srv.new_session line inside ServerManager.new_session().
• When running kill-all-robot-servers, it returns the error message error connecting to /tmp/tmux-0/ServerManager (No such file or directory).

Thanks in advance!

[jr-b-reiterer]

Hi @szhaovas,

have you tried replacing gui=True by gui=False in the environment initialization?

[szhaovas]

Hi @jr-b-reiterer,

Thank you for the reply. Yes, I replaced gui=True with gui=False. The test.py file in the forked repo I shared above contains the test script I was running.

[jr-b-reiterer]

When I test with your image, the behaviour is different: I get past the lines from your screenshot, but then the reset fails. The warning from gym I get there gave me a hint that you are using a too new version of gym, 0.26. robo-gym in the present version is compatible with gym up to 0.21 only because of their API change. (An upgrade of robo-gym is in the works internally.)

Back to your observation: I am using Docker 20.10.21 on Ubuntu 20.04. I am not sure if any difference here could cause the problem. You could test if it is different when you run your test script not in a tmux pane but in a separate terminal that you connect to your running container in addition: docker exec -it <container name> bash

[szhaovas]

Hi @jr-b-reiterer,

I downgraded gym to 0.21, and I am now getting the same error as you. I tried both running docker exec -it <container name> bash and running the test script in a tmux pane, and in both cases, I am no longer stuck at "Starting new robot server", but get an error at reset. Do you know how I might fix the reset error? Thanks!