containerd VS sysbox

Containerd and nerdctl

Kubernetes on the backend used to utilize docker for much of its container runtime solutions. One of the modular features of Kubernetes is the ability to utilize a Container Runtime Interface or CRI. The problem was that Docker didn't really meet the spec properly and they had to maintain a shim to translate properly. Instead users could utilize the popular containerd or cri-o runtimes. These follow the Open Container Initiative or OCI's guidelines on container formats.

Container Engine: A runtime that executes and manages containers. Docker and containerd are popular container engines.

Multiple container runtimes are supported, like conatinerd, cri-o, or other CRI compliant runtimes.

This is a failed attempt to upstream part of containerd changes: https://github.com/containerd/containerd/pull/8789

Other part of containerd changes waits for gods-know-what: https://github.com/containerd/containerd/pull/9054

But I haven't gave up yet.

containerd is required by kubernetes to handle containers on its behalf. A big thanks to the HostAfrica blog for the information on setting containerd up for debain. So the containerd install will need to happen on both the WSL2 instance and the Raspberry Pis. For WSL2 you can just install containerd directly:

The context deadline exceeded: unknown is also in containerd, and is a known problem.

Get:1 https://download.docker.com/linux/ubuntu focal/stable amd64 containerd.io amd64 1.6.21-1 [28.3 MB]

Docker Desktop adds a bunch of stuff to simplify local development and that’s why it has a larger memory footprint. You don’t use that when deploying but something like https://containerd.io/.

You are probably referring to Sysbox (https://github.com/nestybox/sysbox), which I believe will meet your requirements (systemd, inner containers, security, etc).

Btw, Sysbox is already supported in Docker-Desktop (business tier only), so you can easily do what you want with this instruction:

$ docker run -it --rm -e SYSBOX_SYSCONT_MODE=TRUE nestybox/ubuntu-focal-systemd-docker:latest bash

Disclaimer: I'm Sysbox's co-creator and currently working for Docker.

One project in this space that looked quite promising to me is sysbox[0]. I've used them once for a gitlab runner set-up similar to what is described in their blog[1].

It's currently working great and I have not had any major crashes/incidents for at least the past 8 months.

[0]: https://github.com/nestybox/sysbox

[1]: https://blog.nestybox.com/2020/10/21/gitlab-dind.html

Today, things are very different. Docker-in-Docker has a more secure and safe approach with rootless containers and freemium tools like sysbox. Tools like sysbox let you run Docker-in-Docker without the -privileged flag and optimizes specific scenarios, like running multiple nodes of a Kubernetes cluster as ordinary containers.

Right now I am going with sysbox rootless containers. https://github.com/nestybox/sysbox

We’ve been using Sysbox (https://github.com/nestybox/sysbox) for our Buildkite based CI/CD setup, allows docker-in-docker without privileged containers. Paired with careful IAM/STS design we’ve ended up with isolated job containers with their own IAM roles limited to least-privilege.

A good alternative to the VM approach is to use Kubernetes + Sysbox (a next-gen "runc", free, open-source).

But nowadays there is an option to run such software in containers securely. It's called Sysbox, and it's a new "runc" (the piece of software that creates the containers). I am one of the developers, so I am biased, but I think you'll find it helpful.