kubeadm: Single Node Kubernetes Cluster
This tutorial will walk you through bootstrapping a single-node Kubernetes cluster on Google Compute Engine using kubeadm.
Tutorial
Create a single compute instance:
gcloud compute instances create kubeadm-single-node-cluster \
--can-ip-forward \
--image-family ubuntu-1704 \
--image-project ubuntu-os-cloud \
--machine-type n1-standard-4 \
--metadata kubernetes-version=stable-1.8 \
--metadata-from-file startup-script=startup.sh \
--tags kubeadm-single-node-cluster \
--scopes cloud-platform,logging-writeEnable secure remote access to the Kubernetes API server:
gcloud compute firewall-rules create default-allow-kubeadm-single-node-cluster \
--allow tcp:6443 \
--target-tags kubeadm-single-node-cluster \
--source-ranges 0.0.0.0/0
Fetch the client kubernetes configuration file:
gcloud compute scp kubeadm-single-node-cluster:/etc/kubernetes/admin.conf \
kubeadm-single-node-cluster.conf
It may take a few minutes for the cluster to finish bootstrapping and the client config to become readable.
Set the KUBECONFIG env var to point to the kubeadm-single-node-cluster.conf kubeconfig:
export KUBECONFIG=$(PWD)/kubeadm-single-node-cluster.conf
Set the kubeadm-single-node-cluster kubeconfig server address to the public IP address:
kubectl config set-cluster kubernetes \
--kubeconfig kubeadm-single-node-cluster.conf \
--server https://$(gcloud compute instances describe kubeadm-single-node-cluster \
--format='value(networkInterfaces.accessConfigs[0].natIP)'):6443
Verification
List the Kubernetes nodes:
kubectl get nodes
NAME STATUS ROLES AGE VERSION
kubeadm-single-node-cluster Ready master 35m v1.8.0
The node version reflects the kubelet version, therefore it might be different
than the kubernetes-version specified above.
Find out Kubernetes API server version:
kubectl version --short
Client Version: v1.8.0
Server Version: v1.8.0
Create a nginx deployment:
kubectl run nginx --image nginx:1.13 --port 80
Expose the nginx deployment:
kubectl expose deployment nginx --type LoadBalancer
Cleanup
gcloud compute instances delete kubeadm-single-node-cluster
gcloud compute firewall-rules delete default-allow-kubeadm-single-node-cluster
rm kubeadm-single-node-cluster.conf