Frequently Asked Questions (FAQs)

What is the purpose of this new Linux distribution?

The purpose of SimpleK8s is to provide a hassle-free Linux operating system specifically designed for production-grade Kubernetes clusters. It ensures seamless rolling upgrades without any unpleasant surprises or unnecessary software.

What are the system requirements for installing and running this Linux distribution?

The system requirements for different scenarios are as follows:

  • Bare minimum to boot:
    • 1 CPU
    • 128Mb Storage
    • 128Mb RAM.
  • Minimum recommended:
    • 1 CPU
    • 512Mb storage
    • 128Mb RAM
  • Kubernetes 1.37 Control-Plane:
    • 2 CPUs
    • 4Gb storage
    • 3Gb RAM
  • Kubernetes 1.37 Worker:
    • 1 CPU
    • 1Gb storage
    • 1Gb RAM

Is this Linux distribution compatible with my hardware and peripherals?

SimpleK8s is designed to run a lean Kubernetes cluster, so it does not include out-of-scope kernel drivers and firmware, such as sound and HID systems. However, you can compile your own flavor or use extensions to include additional functionality — see supported platforms and integrations.

What desktop environments or window managers does this Linux distribution support?

SimpleK8s does not include any desktop environments. You can use the TTY console or access the web UI at https://node-ip:5443.

Can I dual-boot this Linux distribution with another operating system?

Yes, you can dual-boot SimpleK8s with another operating system. SimpleK8s is distributed as one file that can be booted using any BIOS or UEFI boot manager. We distribute a raw storage image too that includes the SimpleK8s kernel image, GRUB as boot manager (BIOS and UEFI), and a Microsoft-signed shim for secure boot.

What package manager does this Linux distribution use?

SimpleK8s does not include a package manager. However, you can run any container of your choice. SimpleK8s utilizes Containerd and Nerdctl as a Docker replacement (instead of execute the command docker, use nerdctl). You can also run your preferred distribution as a container inside SimpleK8s. For example, the script /usr/local/bin/toolbox launches a privileged Linux Alpine with the host filesystem / mounted at /host.

Are there any unique features or applications included in this Linux distribution?

Yes, SimpleK8s includes the following unique applications:

  • Web installation guide: An optional web UI (the nodectl wizard) running at :5443 that assists you in the installation and setup of your Kubernetes cluster. You can utilize kubeadm instead.
  • nodectl: A program that checks and upgrades the SimpleK8s kernel image.

How often are updates and security patches released for this Linux distribution?

SimpleK8s is a rolling distro: every time one of its components gets a new release — a new Kubernetes version, a new kernel LTS, containerd, etc. — CI/CD builds a new image and publishes it. If Kubernetes 1.38.0 came out tomorrow, there would be a new SimpleK8s release with it in a few days.

Each image is promoted through channels as the community validates it:

  • dev: freshly published by CI/CD; the newest, not yet validated.
  • rolling: being promoted; already passed basic validation.
  • stable: validated by the community — successful reports with fully functional clusters (single and multi-node, control plane and worker roles) — and ready for production.

This procedure is replicated for each supported platform: x86-64, rpi4 and rpi5.

Is there an active and helpful community around this Linux distribution for support and troubleshooting?

Yes. The code lives at github.com/simplek8s; questions, ideas and feedback are welcome in the community discussions, and you can also reach us at community@simplek8s.org.

Is SimpleK8s backed by a company or do you provide commercial support?

No: SimpleK8s is a non-profit, community-driven project and there is no commercial support with SLA. If you need enterprise support, K3s is backed by Rancher/SUSE and Microk8s by Canonical, and both offer commercial plans.

If what you need is a stack you control — signed, immutable, no lock-in — with rolling distro upgrades and community support, SimpleK8s is the option.

Which storage and networking backends has the distro been tested with?

At least the following:

  • Storage: Ceph (CephFS and CephRBD) and NFS.
  • Networking: Calico and MetalLB.

The cluster is plain Kubernetes, so any standard CSI/CNI works as usual. If a component needs extra kernel modules not in the base image, you can compile your own flavor.

Can I deploy an HA cluster?

Yes. The web installation guide shows how to join a second control plane node (and more) with the nodectl wizard, and the SimpleK8s Controller reboots nodes with control-plane awareness: workers first, at most one control plane at a time, and PodDisruptionBudget-aware.

Are there any known issues or limitations with this Linux distribution that I should be aware of?

SimpleK8s operate using an /usr read-only, and a / memory-backed storage. To ensure proper functionality, certain directories are bind-mounted at /var/${DIRECTORY}, including /etc, /home, /mnt, /usr/local, /usr/libexec, /root, and /opt. It is essential to mount a persistent storage at /var to maintain data integrity and preserve configurations. Please keep this in mind while working with SimpleK8s.