Using Multi-Node Clusters (original) (raw)

Overview

This tutorial will show you how to start a multi-node clusters on minikube and deploy a service to it.

Prerequisites

minikube 1.10.1 or higher
kubectl

Caveat

Default host-path volume provisioner doesn’t support multi-node clusters (#12360). To be able to provision or claim volumes in multi-node clusters, you could use CSI Hostpath Driver addon.

Tutorial

Start a cluster with 2 nodes in the driver of your choice:

minikube start --nodes 2 -p multinode-demo

😄 [multinode-demo] minikube v1.18.1 on Opensuse-Tumbleweed ✨ Automatically selected the docker driver 👍 Starting control plane node multinode-demo in cluster multinode-demo 🔥 Creating docker container (CPUs=2, Memory=8000MB) ... 🐳 Preparing Kubernetes v1.20.2 on Docker 20.10.3 ... ▪ Generating certificates and keys ... ▪ Booting up control plane ... ▪ Configuring RBAC rules ... 🔗 Configuring CNI (Container Networking Interface) ... 🔎 Verifying Kubernetes components... ▪ Using image gcr.io/k8s-minikube/storage-provisioner:v5 🌟 Enabled addons: storage-provisioner, default-storageclass 👍 Starting node multinode-demo-m02 in cluster multinode-demo 🔥 Creating docker container (CPUs=2, Memory=8000MB) ... 🌐 Found network options: ▪ NO_PROXY=192.168.49.2 🐳 Preparing Kubernetes v1.20.2 on Docker 20.10.3 ... ▪ env NO_PROXY=192.168.49.2 🔎 Verifying Kubernetes components... 🏄 Done! kubectl is now configured to use "multinode-demo" cluster and "default" namespace by default∗Getthelistofyournodes:* Get the list of your nodes:∗Getthelistofyournodes:NAME STATUS ROLES AGE VERSION multinode-demo Ready control-plane,master 99s v1.20.2 multinode-demo-m02 Ready

73s v1.20.2∗Youcanalsocheckthestatusofyournodes:‘‘‘minikubestatus−pmultinode−demo‘‘‘* You can also check the status of your nodes:

minikube status -p multinode-demo

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kubectl apply -f hello-deployment.yaml

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kubectl apply -f hello-svc.yaml


hello-695c67cf9c-frcvw 1/1 Running 0 22s 10.244.0.3 multinode-demo <span class="katex-display"><span class="katex"><span class="katex-mathml"><math xmlns="http://www.w3.org/1998/Math/MathML" display="block"><semantics><mrow><mo>∗</mo><mi>L</mi><mi>o</mi><mi>o</mi><mi>k</mi><mi>a</mi><mi>t</mi><mi>o</mi><mi>u</mi><mi>r</mi><mi>s</mi><mi>e</mi><mi>r</mi><mi>v</mi><mi>i</mi><mi>c</mi><mi>e</mi><mo separator="true">,</mo><mi>t</mi><mi>o</mi><mi>k</mi><mi>n</mi><mi>o</mi><mi>w</mi><mi>w</mi><mi>h</mi><mi>a</mi><mi>t</mi><mi>U</mi><mi>R</mi><mi>L</mi><mi>t</mi><mi>o</mi><mi>h</mi><mi>i</mi><mi>t</mi><mi mathvariant="normal">‘</mi><mi mathvariant="normal">‘</mi><mi mathvariant="normal">‘</mi><mi>m</mi><mi>i</mi><mi>n</mi><mi>i</mi><mi>k</mi><mi>u</mi><mi>b</mi><mi>e</mi><mi>s</mi><mi>e</mi><mi>r</mi><mi>v</mi><mi>i</mi><mi>c</mi><mi>e</mi><mi>l</mi><mi>i</mi><mi>s</mi><mi>t</mi><mo>−</mo><mi>p</mi><mi>m</mi><mi>u</mi><mi>l</mi><mi>t</mi><mi>i</mi><mi>n</mi><mi>o</mi><mi>d</mi><mi>e</mi><mo>−</mo><mi>d</mi><mi>e</mi><mi>m</mi><mi>o</mi><mi mathvariant="normal">‘</mi><mi mathvariant="normal">‘</mi><mi mathvariant="normal">‘</mi></mrow><annotation encoding="application/x-tex">* Look at our service, to know what URL to hit

minikube service list -p multinode-demo

curl http://192.168.49.2:31000

```∗Let’shittheURLafewtimesandseewhatcomesback‘‘‘curlhttp://192.168.49.2:31000‘‘‘Hello from hello-695c67cf9c-frcvw (10.244.0.3) curl http://192.168.49.2:31000 Hello from hello-695c67cf9c-bzrzk (10.244.1.2) curl http://192.168.49.2:31000 Hello from hello-695c67cf9c-bzrzk (10.244.1.2) curl http://192.168.49.2:31000 Hello from hello-695c67cf9c-frcvw (10.244.0.3)∗Multiplenodes!∗ReferencedYAMLfiles* Multiple nodes!

Referenced YAML files∗Multiplenodes!∗ReferencedYAMLfilesapiVersion: apps/v1 kind: Deployment metadata: name: hello spec: replicas: 2 strategy: type: RollingUpdate rollingUpdate: maxUnavailable: 100% selector: matchLabels: app: hello template: metadata: labels: app: hello spec: affinity: # ⬇⬇⬇ This ensures pods will land on separate hosts podAntiAffinity: requiredDuringSchedulingIgnoredDuringExecution: - labelSelector: matchExpressions: [{ key: app, operator: In, values: [hello] }] topologyKey: "kubernetes.io/hostname" containers: - name: hello-from image: pbitty/hello-from:latest ports: - name: http containerPort: 80 terminationGracePeriodSeconds: 1$$ apiVersion: v1 kind: Service metadata: name: hello spec: type: NodePort selector: app: hello ports: - protocol: TCP nodePort: 31000 port: 80 targetPort: http$$