k3s vs k0s vs MicroK8s

All three are lightweight Kubernetes distributions with different trade-offs.

k3s is not the only lightweight Kubernetes. The main alternatives are k0s and MicroK8s. All three are conformant Kubernetes, so your manifests work on any of them.

DistroMaintainerNotable trait
k3sSUSE / RancherSingle binary, batteries included, huge edge community
k0sMirantisSingle binary, no host dependencies, minimal defaults
MicroK8sCanonicalSnap-based, add-ons enabled via commands

How to choose

  • Pick k3s for edge, IoT, and a rich set of built-in defaults.
  • Pick k0s if you want a very bare control plane you assemble yourself.
  • Pick MicroK8s if you live in the Ubuntu/snap ecosystem.

Example

Example · bash
# Roughly equivalent "install a cluster" commands

# k3s
curl -sfL https://get.k3s.io | sh -

# k0s
curl -sSLf https://get.k0s.sh | sh && sudo k0s install controller --single

# MicroK8s (Ubuntu)
sudo snap install microk8s --classic

When to use it

  • An architect chooses k3s over MicroK8s for an air-gapped deployment because k3s provides an official single-binary offline install path.
  • A team evaluates k0s as an alternative to k3s when they need a CNI-agnostic install without any bundled networking components.
  • A CI system benchmarks k3s against k3d and MicroK8s startup time to select the fastest option for ephemeral test clusters.

More examples

Check k3s binary size

Shows the k3s binary size to illustrate how it compares to k0s (similar) and MicroK8s (larger via snap).

Example · bash
# k3s: single binary ~60 MB
ls -lh $(which k3s)
k3s --version
# Compare: k0s single binary ~60 MB, MicroK8s uses snaps (~200 MB+)

Time cluster startup

Measures total install and Ready time for k3s, useful when comparing startup speed against k0s or MicroK8s.

Example · bash
time (curl -sfL https://get.k3s.io | sh - && \
  kubectl wait --for=condition=Ready node --all --timeout=60s)

Compare bundled components

Lists k3s kube-system pods to see which networking and ingress components ship by default versus the alternatives.

Example · bash
# k3s includes: Flannel, Traefik, ServiceLB, CoreDNS, metrics-server, local-path
kubectl get pods -n kube-system
# k0s and MicroK8s have different default add-on sets; check their docs

Discussion

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