In Azure IoT Edge docker containers are the deployment vehicle for the runtime and custom logic. You define the stack of modules in the deployment configuration through the Azure Portal. If the deployment is submitted the edge agent is grabbing the new deployment configuration and applies the state to the local edge device.
During this process the docker containers will be created on the edge device. This creation process can be modified using the createOptions using the portal (or later the command line) like shown in this screenshot
You can use all container creation options provided by the Docker API. To expose port 8081 to the docker host you enter
Verifying createOptions during Startup
You can docker logs -f edgeAgent to check if the containers created will include the specified createOptions for your deployment. Below you see the output of the port 8081 binding.