k3s vs Kubernetes (k8s): Which Should You Self-Host?

Quick Verdict

k3s is the right choice for most self-hosters. It’s a certified Kubernetes distribution that runs in 512 MB RAM, installs in 30 seconds, and is fully compatible with the Kubernetes API. Standard Kubernetes (kubeadm/vanilla k8s) only makes sense if you need specific features k3s strips out — like etcd clustering or custom CNI plugins for large-scale production.

Overview

k3s is a lightweight Kubernetes distribution built by Rancher Labs (now SUSE). It packages the entire Kubernetes control plane into a single binary (~70 MB), replaces etcd with SQLite by default, and bundles Traefik, CoreDNS, and a local storage provisioner. It’s CNCF-certified — any Kubernetes workload runs on it without modification.

Kubernetes (k8s) refers to the standard upstream Kubernetes distribution, typically installed via kubeadm. It runs etcd for state storage, requires manual CNI installation, and has a multi-binary control plane (kube-apiserver, kube-controller-manager, kube-scheduler, etcd). It’s designed for large-scale production clusters.

Feature Comparison

Feature	k3s	Kubernetes (k8s)
Install time	~30 seconds	15-30 minutes
Binary size	~70 MB (single binary)	~300 MB (multiple binaries)
Control plane RAM	~512 MB	~2 GB minimum
Default datastore	SQLite (single node) or etcd	etcd (required)
Bundled CNI	Flannel	None (manual install)
Bundled ingress	Traefik	None (manual install)
Bundled DNS	CoreDNS	CoreDNS
Bundled load balancer	ServiceLB (Klipper)	None
Bundled storage	Local path provisioner	None
ARM support	Full (arm64, armhf)	Limited (community images)
CNCF certified	Yes	Yes
HA support	Yes (embedded etcd or external DB)	Yes (stacked or external etcd)
Auto-upgrades	system-upgrade-controller	Manual or custom
License	Apache 2.0	Apache 2.0

Installation Complexity

k3s installs with a single command:

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

That’s it. In 30 seconds you have a working single-node Kubernetes cluster with Traefik, CoreDNS, and local storage ready to go. Adding worker nodes is one command per node.

Kubernetes via kubeadm requires:

1. Install container runtime (containerd)
2. Install kubeadm, kubelet, kubectl
3. Disable swap
4. Run kubeadm init with configuration
5. Install a CNI plugin (Calico, Flannel, Cilium)
6. Install an ingress controller
7. Install a storage provisioner
8. Configure kubectl access

Winner: k3s. Not even close. k3s gets you from zero to cluster in 30 seconds. kubeadm takes 15-30 minutes even for experienced operators.

Performance and Resource Usage

Metric	k3s	Kubernetes (kubeadm)
Control plane RAM	512 MB	2+ GB
Control plane CPU	1 core	2+ cores
Minimum disk	2 GB	10+ GB
Worker node RAM	256 MB	1+ GB
Startup time	~5 seconds	~30 seconds
Runs on Raspberry Pi	Yes (officially supported)	Technically possible, not recommended

k3s achieves this by:

• Using SQLite instead of etcd (for single-node setups)
• Bundling everything into one binary
• Removing legacy/alpha APIs and cloud provider code
• Using containerd directly (no Docker shim)

Community and Support

Metric	k3s	Kubernetes
GitHub stars	29k+	115k+
Maintained by	SUSE/Rancher Labs	CNCF / Many companies
Documentation	docs.k3s.io	kubernetes.io/docs
Release cadence	Tracks upstream k8s releases	~3 releases/year
Commercial support	SUSE Rancher	Many vendors
Ecosystem	Full k8s ecosystem compatibility	The ecosystem itself

k3s tracks upstream Kubernetes closely — typically within weeks of each upstream release. The full Kubernetes ecosystem (Helm charts, operators, tools) works identically on k3s.

Use Cases

Choose k3s If…

• You’re self-hosting on a single server or small cluster
• You want Kubernetes on a Raspberry Pi or edge device
• You want a working cluster in under a minute
• You want batteries-included (ingress, DNS, storage, load balancer)
• You’re running on ARM hardware
• You want low resource overhead
• You’re learning Kubernetes

Choose Standard Kubernetes If…

• You need etcd for multi-master HA in large clusters (50+ nodes)
• You need custom CNI (Cilium, Calico with advanced network policies)
• You need specific API features k3s doesn’t enable by default
• You’re training for CKA/CKAD certification and want vanilla experience
• You’re running a production cluster with dedicated infrastructure
• Your organization mandates upstream Kubernetes

Final Verdict

k3s is Kubernetes for the real world. It’s the same API, the same workloads, the same ecosystem — just without the operational overhead of vanilla Kubernetes. For self-hosters, homelab users, and small teams, there’s no reason to run standard kubeadm Kubernetes.

The only legitimate reasons for vanilla k8s are large-scale production requirements (50+ nodes, custom networking with Cilium) or certification training. For everything else, k3s is the answer.

FAQ

Is k3s “real” Kubernetes?

Yes. k3s is CNCF-certified Kubernetes. It passes the same conformance tests as any other distribution. Helm charts, kubectl, operators, and the entire Kubernetes ecosystem work identically.

Can I upgrade from k3s to standard Kubernetes later?

Your workloads (Deployments, Services, ConfigMaps) are portable — you can apply the same YAML to any Kubernetes cluster. The upgrade path is to deploy a new cluster and migrate workloads, not an in-place upgrade.

Does k3s support multi-node clusters?

Yes. k3s supports multi-node clusters with dedicated server (control plane) and agent (worker) nodes. For HA, you can use embedded etcd (3+ server nodes) or an external database (MySQL, PostgreSQL).

What did k3s remove from Kubernetes?

Legacy and alpha APIs, in-tree cloud provider code, and in-tree storage drivers. It replaces etcd with SQLite (single-node) and bundles containerd directly. No features that self-hosters need were removed.

Related

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• k3s vs k0s
• Docker Swarm vs Kubernetes
• Nomad vs Kubernetes
• Best Self-Hosted Container Orchestration
• Container Orchestration Basics