When setting up a Home Assistant Docker container, you might encounter issues with port visibility, meaning that even if your container is running perfectly, you can’t access it through the assigned port. This article walks through resolving such issues, focusing on the Home Assistant Docker container which I have faced during my setup.

Before diving into the scenario, let’s walk through the steps to set up and run Home Assistant on Docker:

Home Assistant is an open-source home automation platform that focuses on privacy and local control. It runs on most systems and provides the capability to observe, control, and automate devices around the home. The official Home Assistant Docker image is homeassistant/home-assistant.

Setting up Home Assistant

Ensure Docker is Installed

Before running any Docker commands, ensure that Docker is properly installed on your system. If not, download and install Docker from the official website or through your system’s package manager.

Pull the Home Assistant Docker Image

You will need to pull the official Home Assistant Docker image to your local machine. This can be done with the following command:

docker pull homeassistant/home-assistant

Set Up the Configuration Directory

Home Assistant stores its configuration in a directory, which you will map to a volume in your Docker container. If you’re new to Home Assistant, you’ll want to create a new directory for this purpose. The given command in the scenario maps ~/homeassistant on the host to /config in the container, so make sure this directory exists:

mkdir ~/homeassistant

Run the Home Assistant Docker Container

Use the docker run command to start a new Home Assistant container. The command in the scenario already covers this, but here it is again for reference:

docker run -d --name homeassistant -v ~/homeassistant:/config --net=host homeassistant/home-assistant

Access Home Assistant

If everything runs correctly, you should be able to access Home Assistant in your browser by navigating to:

http://<your-server-ip>:8123

Now that we have the basics covered, let’s proceed to the scenario where there might be issues with port visibility.

Scenario

The user attempted to run the container using the following command:

docker run -d --name homeassistant -v ~/homeassistant:/config --net=host homeassistant/home-assistant

However, accessing the Home Assistant UI through port 8123 was not successful.

Resolution

A modification of the run command to explicitly publish the port resolved the issue:

docker run -p 8123:8123 homeassistant/home-assistant:latest

When using --net=host, the container shares the host’s network stack, and the -p (publish) flag is not valid, as all ports are implicitly published. However, this can sometimes lead to port visibility issues due to conflicts or restrictions in the network environment.

Explicitly publishing the port using -p 8123:8123 makes it accessible to the host and avoids conflicts, making the Home Assistant UI accessible via http://your_host_ip:8123.

Additional Debugging Steps

If you still encounter issues accessing the port, consider the following steps:

1. Check if the Container is Running:

   docker ps
   

2. Review the Container Logs:

   docker logs homeassistant
   

3. Inspect the Container’s Network and Port Settings:

   docker inspect homeassistant
   

When deploying Home Assistant or any other services in a Docker container, being explicit about port mappings can help avoid accessibility issues. While using --net=host simplifies the networking setup by sharing the host’s network, it may lead to unintended port conflicts or visibility issues.