From Docker Desktop To Rancher Desktop: Quick And Simple

assorted-color filed intermodal containers — Photo by frank mckenna on Unsplash

As most of you already know, the 31st of January is the last day to use Docker Desktop without applying the new licensing model that pretty much generates a cost for any company usage. Of course, it is still free to use for open-source and small companies, but it is better to meet the requirements using Docker official documentation.

So because of that situation, I started a journey to find an alternative to Docker Desktop because I used docker-desktop a lot. The primary use I do is to startup server-like things for temporary usage that I don’t like to have installed in my machine to keep it as clean as possible (even though this is not always true, but it is an attempt).

So, on that search, I discovered Rancher Desktop was released not a long time ago and promised to be the most suitable alternative. The goal of this post is not to compare both platforms, but if you like to have more information I leave here a post that can provide it to you:

Rancher Desktop

Container management to build, push, and pull images and run containers. It uses the same container runtime as Kubernetes. Built images are immediately available to use in your local workloads without any pushing, pulling, or copying.

The idea here is to talk more about the journey of that migration. So I installed the Rancher Desktop 1.0.0 on my Mac and the installation was very, very easy. The main difference with Docker Desktop is that Rancher Desktop is built with Kubernetes in mind and for Docker Desktop, that came as an afterthought. So, by default we will have a Kubernetes environment running in our system, and we can even select the version of that cluster as you can see in the picture below:

But also in Rancher, they noticed the opportunity window they have in front of them, and they were very aggressive in providing an easy migration path from Docker Desktop. And the first thing you will notice is that you can configure Docker Desktop to be compliant with the Docker CLI API as you can see in the picture below.

This is not enabled by default, but it is very easy to do it and it will make you not need to change all your “docker-like” commands (docker build, docker ps.. ) so it will smooth a lot of the transition.

Maybe in the future, you want to move away from everything resembling docker even at the client-side and move to a Containers kind of approach, but for now, what I needed is to simplify the process.

So, after enabling that and restarting my Rancher Desktop, I can type my commands as you can see in the picture below:

So, the only thing I need to do is migrate my images and containers. Because I’m not a pure docker usage, I don’t follow sometimes the thing to have your container stateless and using volumes especially when you are doing a small use for some time and that’s it. So, that means that some of my containers also need to be moved to the new platform to avoid any data loss.

So, my migration journey had different steps:

First of all, I will commit the stateful containers that I need to keep on the new system using the command docker commit with the documentation that you can find here:

Then, I will export all the images that I have now in TAR files using the command docker save with the documentation that you can find it here:

And finally, I will load all those images on the new system using docker load command to have it available there. Again, you can find the documentation of that specific command here

To automate a little bit the process even that I don’t have much images loaded because I try to clean up from time to time using the docker system prune command:

I prefer not to do it manually, so I will use some simple scripts to do the job.

So, to perform the export job I need to run the following command:

docker image ls -q | xargs -I {} docker image save {} -o {}.tar

This script will save to have all my images on different tar files into a specific folder. Now, I just need to run the following command from the same folder I had run the previous one to have all the images back into the new system:

find . -name "*.tar" -exec docker load -i {} \;

The reason why I’m not doing both actions at the same time is that I need to have running Docker Desktop for the first part and Rancher Desktop for the other. So even though I can automate that as well, I think it is not worth it.

And that’s it, now I can remove the Docker Desktop from my laptop, and my life will continue to be the same. I will try to provide more feedback on how it feels, especially regarding resource utilization and similar topics in the near future.

From Docker Desktop to Rancher Desktop: Quick and Simple

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