Single-Node kubeadm Cluster Setup

Installation and Cluster Builds / Guide 7 of 103 / Beginner

• OSUbuntu 26.04 LTS
• Kernel7.0.0-29-generic
• Kubernetes1.36.4
• containerd2.2.6
• Calicov3.32.1
• TimeAbout 40 min
• Reviewed21 August 2026

Written against the versions above. Download sizes, image digests, timings and pod name suffixes differ on every run. Patch versions move weekly, so treat these as what was on the machine rather than as requirements.

Before you start

• An Ubuntu 26.04 machine with at least 2 CPUs and 2 GB of RAM. kubeadm refuses to start below that, and on one machine the control plane and your workloads share whatever you give it.
• A user with sudo rights, and a hostname unique on the network: kubeadm uses the hostname as the node name.
• A fixed address, from a static config or a DHCP reservation. The API server certificate is issued for the address you advertise, so a control plane that moves needs its certificates regenerating.
• Outbound HTTPS to pkgs.k8s.io, registry.k8s.io, quay.io and raw.githubusercontent.com.
• Know your LAN range before you start. It decides the pod CIDR, and picking one that overlaps is the most common way to end up with a cluster that looks healthy and cannot route.

1. 1

   Check the machine meets kubeadm's floor

2. 2

   Turn swap off, and keep it off

3. 3

   Load the kernel modules and set the sysctls

4. 4

   Point containerd at the systemd cgroup driver

5. 5

   Add the Kubernetes apt repository

6. 6

   Install kubelet, kubeadm and kubectl, then hold them

7. 7

   Initialise the control plane

8. 8

   Get a kubeconfig, and see the cluster refuse to be Ready

9. 9

   Install Calico, and wait for its CRDs before configuring it

10. 10

    Remove the control-plane taint

11. 11

    Prove it works: DNS and Service routing

12. 12

    Clean up the smoke test

Official sources

• Installing kubeadm
• Creating a cluster with kubeadm
• Container runtimes and cgroup drivers
• Calico: install with the Tigera operator