In this post, I will walkthrough the basic steps needed in order to tune the kernel parameters in the docker image of your desired distro.

Pull the docker image from the dockerhub.

docker pull ubuntu

Execute the command

docker run -it --rm --privileged ubuntu

-it options tells it run in interactive mode; –rm tells that the container must be destroyed when we exit the system; –privileged needs to be set as we are trying to make changes to the proc and sys directories for which the docker does not allow any changes when in normal mode. Therefore, we need privileged mode.

Once you are into the system, you can now install any packages you want. Make all the desired configurations. As an example, let’s enable IP forwaring on this image. Execute

sysctl -w net.ipv4.ip_forward=1

Keep this terminal open.

Open another terminal. Now, let’s try to make a new image which will have these settings.

docker commit <containerid> <imagename>:<imagetag>

docker commit fe1799e6987e tuning:latest

You can now view the images by typing

docker images -a

If you want to push the image to the dockerhub then, login and create a tag and push.

docker login

docker tag tuning:latest rohittahiliani/practice

docker push rohittahiliani/practice