FAQ on Installing SDK via Docker on Windows

This FAQ page addresses the common issues users face with installing Docker and the Plate Recognizer SDK.

Q1: How can I be sure that Docker is working?
Q2: What does it mean that the Docker daemon is not running?
Q3: I have Virtual Box installed on my system. Since I installed Docker, I cannot execute any virtual machines anymore.
Q4: Is my Virtual Box data lost?
Q5: How do I check how much disk resources Docker is currently using?

Q6: How can I know if the SDK container is currently running?
Q7: What should I do with a “License file not found” error?
Q8: What is a “connection refused” error?
Q9: What does this message mean: “This license has already been installed. It cannot be used.”?
Q10: How do I change the port of the container?

Q1. How can I be sure that Docker is working?

Open a Command Line (CMD) and type: docker version

You can also type this in the Command Line: docker run hello-world

Q2. What does it mean that Docker daemon is not running?

The message: “Docker: error during connect: Post… This error may also indicate that docker daemon it not running” means that Docker is not running in your system.

You will first have to execute Docker. Please go to Step 1 on How to Install Docker.

After you successfully install and start to run Docker, you will get the following message:

Q3. I have a Virtual Box installed on my system. Since I installed Docker, I cannot execute any of my virtual machines anymore. Why?

Be aware that enabling Docker in your system will prevent you to keep using Virtual Box.

When Hyper-V technology is enabled, it interferes with Virtual Box.

More information about this in docs.docker.com/docker-for-windows/install

Q4. Is my Virtual Box lost?

No. Your Virtual Box is not lost. You just cannot execute a virtual machine once you have Docker on.

Q5. How do I check how much disk resources Docker is using?

Go to the Command Line (CMD) and type: docker system df

Q6. How can I check if the SDK container is running correctly?

Go to the Command Line (CMD) and type: docker ps

Q7. What should I do with a “License file not found” error?

Make sure you have replaced the MY_KEY with your key in the run command. Refer to Step 20 of the Installing SDK via Docker on Windows

Q8. What is a “connection refused” error when I am trying to upload images with curl?

You are probably receiving this message because the container is not running.

To verify that type “docker ps” in the Command Line (CMD) in the terminal to see the status of containers. It should look like this (1 container running in port 8080):

If the status doesn’t show any containers at all, then the SDK container is not actually running in your system.

You will need to first run it. Refer to Step 20 of the Installing SDK via Docker on Windows.

Q9. What does “you have a container running with this license” mean?

This means that you currently have a container running with this license–perhaps on another machine.

If you need to install the SDK in another machine, please uninstall this one first. Refer to Step 23 of the Installing to Uninstall SDK via Docker on Windows to uninstall the SDK..

Or, go app.platerecognizer.com/accounts/plan to add another license for this machine.

Q10. How do I change the port of the container?

If you are already using port 8080, then you can change the port of the container by running this Command Line (CMD):

docker run –rm -t -v license:/license -e TOKEN=MY_TOKEN -e UNINSTALL=1 -p 8085:8080 platerecognizer/alpr

The -p 8085:8080 part will bind the port 8085 of your host machine with the port 8080 inside the container.

Need Help with LPR?

Let us know and we’d be happy to assist.