K3s vs Kubernetes

K3s is a certified, lightweight Kubernetes distribution for IoT and edge computing. It runs self-hosted on Linux and is released for x86_64, ARMv7, and ARM64. The distribution arrives as one binary or a minimal container image; the site describes the binary as under 70 MB, while documentation says under 100 MB. Documented uses include edge systems, homelabs, IoT, continuous integration, development, ARM single-board computers, air-gapped environments, and embedded Kubernetes. SQLite is the default datastore, with etcd, MySQL, and Postgres available. K3s packages containerd or cri-dockerd, Flannel, CoreDNS, Traefik, ServiceLB, Kube-router, local-path-provisioner, and Spegel. High-availability deployments can use embedded storage or external MySQL, PostgreSQL, or etcd. Air-gapped installation supports private registries, manually deployed images, or an embedded registry mirror. Security guidance includes hardening and CIS self-assessment material. Automated Kubernetes-native upgrades use Rancher’s system-upgrade-controller.

Kubernetes is an open-source system for automating deployment, scaling, and management of containerized applications. It supports stateless, stateful, and data-processing workloads, and can run locally, in a cloud, or in a datacenter; users can also choose a managed service rather than operate a cluster themselves. It coordinates gradual updates while monitoring application health and can roll back a change if something goes wrong. Pods receive IP addresses and groups of Pods can share a DNS name, with load balancing across them. Kubernetes can mount storage from local, public-cloud, or network systems such as iSCSI or NFS. Secrets and configuration can be updated without rebuilding images. Scaling can be manual or automatic based on CPU use. Security mechanisms include Secrets, Pod security standards, RuntimeClasses, network policies, admission controllers, and audit logging. Kubernetes is free, with a listed plan price of free. It does not include application-level services such as databases, message buses, caches, or cluster storage systems.