Hi Bruno,
Yes, you can indeed do it like that.
So, open a terminal, navigate to your Isaac SIM folder and set the environment variables as:
export ROS_MASTER_URI = ####
export ROS_IP = ###
Then launch manually Isaac SIM with:
./isaac-sim.sh
(or other alternatives if you are running headless for example)
Alternatively, you could set these through python: if you are using any of our python ROS samples or your own scripts with something like:
import os
os.environ[‘ROS_IP’] = YOUR_IP
print(os.getenv(‘ROS_IP’))
Lastely, if you are using docker containers you can pass it as an argument in the docker run command with --env ROS_IP=###