Kubernetes

Learn to deploy a Kubernetes cluster in 30 minutes using KubeAdm

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Learn to deploy a Kubernetes cluster in 30 minutes using KubeAdm

Learn to deploy a Kubernetes cluster in 30 minutes using KubeAdm

**Pre-Requisites: **

Create 3 VMs with 2 core 8 GB and 10-100 GB HDD

1. Docker set up in master and nodes**

1a.** Login into master and update your existing list of packages  

.fusion-syntax-highlighter-82 > .CodeMirror, .fusion-syntax-highlighter-82 > .CodeMirror .CodeMirror-gutters {background-color:var(--awb-color1);}.fusion-syntax-highlighter-82 > .CodeMirror .CodeMirror-gutters { background-color: var(--awb-color2); }.fusion-syntax-highlighter-82 > .CodeMirror .CodeMirror-linenumber { color: var(--awb-color8); }Copy to ClipboardSyntax Highlighter$ sudo apt update 1b. Install the prerequisite packages which let apt to use packages over HTTPS 

.fusion-syntax-highlighter-83 > .CodeMirror, .fusion-syntax-highlighter-83 > .CodeMirror .CodeMirror-gutters {background-color:var(--awb-color1);}.fusion-syntax-highlighter-83 > .CodeMirror .CodeMirror-gutters { background-color: var(--awb-color2); }.fusion-syntax-highlighter-83 > .CodeMirror .CodeMirror-linenumber { color: var(--awb-color8); }Copy to ClipboardSyntax Highlighter$ sudo apt install apt-transport-https ca-certificates curl software-properties-common -y### 1c. Add the GPG key for the official Docker repository to your system   .fusion-syntax-highlighter-84 > .CodeMirror, .fusion-syntax-highlighter-84 > .CodeMirror .CodeMirror-gutters {background-color:var(--awb-color1);}.fusion-syntax-highlighter-84 > .CodeMirror .CodeMirror-gutters { background-color: var(--awb-color2); }.fusion-syntax-highlighter-84 > .CodeMirror .CodeMirror-linenumber { color: var(--awb-color8); }Copy to ClipboardSyntax Highlighter$ curl -fsSL https://download.docker.com/linux/ubuntu/gpg | sudo apt-key add -### 1d. Add the Docker repository to APT sources    .fusion-syntax-highlighter-85 > .CodeMirror, .fusion-syntax-highlighter-85 > .CodeMirror .CodeMirror-gutters {background-color:var(--awb-color1);}.fusion-syntax-highlighter-85 > .CodeMirror .CodeMirror-gutters { background-color: var(--awb-color2); }.fusion-syntax-highlighter-85 > .CodeMirror .CodeMirror-linenumber { color: var(--awb-color8); }Copy to ClipboardSyntax Highlighter$ sudo add-apt-repository "deb [arch=amd64] https://download.docker.com/linux/ubuntu bionic stable"### 1e. Update the packages with the Docker packages from the newly added repo .fusion-syntax-highlighter-86 > .CodeMirror, .fusion-syntax-highlighter-86 > .CodeMirror .CodeMirror-gutters {background-color:var(--awb-color1);}.fusion-syntax-highlighter-86 > .CodeMirror .CodeMirror-gutters { background-color: var(--awb-color2); }.fusion-syntax-highlighter-86 > .CodeMirror .CodeMirror-linenumber { color: var(--awb-color8); }Copy to ClipboardSyntax Highlighter$ sudo apt update### 1f. Make sure you are about to install from the Docker repo .fusion-syntax-highlighter-87 > .CodeMirror, .fusion-syntax-highlighter-87 > .CodeMirror .CodeMirror-gutters {background-color:var(--awb-color1);}.fusion-syntax-highlighter-87 > .CodeMirror .CodeMirror-gutters { background-color: var(--awb-color2); }.fusion-syntax-highlighter-87 > .CodeMirror .CodeMirror-linenumber { color: var(--awb-color8); }Copy to ClipboardSyntax Highlighter$ sudo apt-cache policy docker-ce### 1g. Run the following command to install Docker    .fusion-syntax-highlighter-88 > .CodeMirror, .fusion-syntax-highlighter-88 > .CodeMirror .CodeMirror-gutters {background-color:var(--awb-color1);}.fusion-syntax-highlighter-88 > .CodeMirror .CodeMirror-gutters { background-color: var(--awb-color2); }.fusion-syntax-highlighter-88 > .CodeMirror .CodeMirror-linenumber { color: var(--awb-color8); }Copy to ClipboardSyntax Highlighter$ sudo apt-get install docker-ce=18.06.3ce3-0~ubuntu -y containerd.io=1.2.2-1 ### 1h. Run the following command to check if the docker is running    .fusion-syntax-highlighter-89 > .CodeMirror, .fusion-syntax-highlighter-89 > .CodeMirror .CodeMirror-gutters {background-color:var(--awb-color1);}.fusion-syntax-highlighter-89 > .CodeMirror .CodeMirror-gutters { background-color: var(--awb-color2); }.fusion-syntax-highlighter-89 > .CodeMirror .CodeMirror-linenumber { color: var(--awb-color8); }Copy to ClipboardSyntax Highlighter$ sudo systemctl status docker### 1i. To avoid sudo requirement in executing the docker command, add your user to docker group    .fusion-syntax-highlighter-90 > .CodeMirror, .fusion-syntax-highlighter-90 > .CodeMirror .CodeMirror-gutters {background-color:var(--awb-color1);}.fusion-syntax-highlighter-90 > .CodeMirror .CodeMirror-gutters { background-color: var(--awb-color2); }.fusion-syntax-highlighter-90 > .CodeMirror .CodeMirror-linenumber { color: var(--awb-color8); }Copy to ClipboardSyntax Highlighter$ sudo usermod -aG docker ${USER}### 1j. To apply the new group membership, run the following command    .fusion-syntax-highlighter-91 > .CodeMirror, .fusion-syntax-highlighter-91 > .CodeMirror .CodeMirror-gutters {background-color:var(--awb-color1);}.fusion-syntax-highlighter-91 > .CodeMirror .CodeMirror-gutters { background-color: var(--awb-color2); }.fusion-syntax-highlighter-91 > .CodeMirror .CodeMirror-linenumber { color: var(--awb-color8); }Copy to ClipboardSyntax Highlighter$ sudo su - ${USER}You will be prompted to enter your user password to continue

1k. Confirm that your user is now added to the docker group by typing

.fusion-syntax-highlighter-92 > .CodeMirror, .fusion-syntax-highlighter-92 > .CodeMirror .CodeMirror-gutters {background-color:var(--awb-color1);}.fusion-syntax-highlighter-92 > .CodeMirror .CodeMirror-gutters { background-color: var(--awb-color2); }.fusion-syntax-highlighter-92 > .CodeMirror .CodeMirror-linenumber { color: var(--awb-color8); }Copy to ClipboardSyntax Highlighter$ id -nGRepeat the above steps for both the nodes.

2. Kubernetes master set up**

2a.** Login to the master and install kubelet, kubeadm and kubectl** **

.fusion-syntax-highlighter-93 > .CodeMirror, .fusion-syntax-highlighter-93 > .CodeMirror .CodeMirror-gutters {background-color:var(--awb-color1);}.fusion-syntax-highlighter-93 > .CodeMirror .CodeMirror-gutters { background-color: var(--awb-color2); }.fusion-syntax-highlighter-93 > .CodeMirror .CodeMirror-linenumber { color: var(--awb-color8); }Copy to ClipboardSyntax Highlighter$ sudo apt-get update && sudo apt-get install -y apt-transport-https curl.fusion-syntax-highlighter-94 > .CodeMirror, .fusion-syntax-highlighter-94 > .CodeMirror .CodeMirror-gutters {background-color:var(--awb-color1);}.fusion-syntax-highlighter-94 > .CodeMirror .CodeMirror-gutters { background-color: var(--awb-color2); }.fusion-syntax-highlighter-94 > .CodeMirror .CodeMirror-linenumber { color: var(--awb-color8); }Copy to ClipboardSyntax Highlighter$ curl -s https://packages.cloud.google.com/apt/doc/apt-key.gpg | sudo apt-key add -.fusion-syntax-highlighter-95 > .CodeMirror, .fusion-syntax-highlighter-95 > .CodeMirror .CodeMirror-gutters {background-color:var(--awb-color1);}.fusion-syntax-highlighter-95 > .CodeMirror .CodeMirror-gutters { background-color: var(--awb-color2); }.fusion-syntax-highlighter-95 > .CodeMirror .CodeMirror-linenumber { color: var(--awb-color8); }Copy to ClipboardSyntax Highlighter$ cat .fusion-syntax-highlighter-96 > .CodeMirror, .fusion-syntax-highlighter-96 > .CodeMirror .CodeMirror-gutters {background-color:var(--awb-color1);}.fusion-syntax-highlighter-96 > .CodeMirror .CodeMirror-gutters { background-color: var(--awb-color2); }.fusion-syntax-highlighter-96 > .CodeMirror .CodeMirror-linenumber { color: var(--awb-color8); }Copy to ClipboardSyntax Highlighter$ sudo apt-get update.fusion-syntax-highlighter-97 > .CodeMirror, .fusion-syntax-highlighter-97 > .CodeMirror .CodeMirror-gutters {background-color:var(--awb-color1);}.fusion-syntax-highlighter-97 > .CodeMirror .CodeMirror-gutters { background-color: var(--awb-color2); }.fusion-syntax-highlighter-97 > .CodeMirror .CodeMirror-linenumber { color: var(--awb-color8); }Copy to ClipboardSyntax Highlighter$ sudo apt-get install -y --allow-change-held-packages kubelet=1.18.15-00 kubeadm=1.18.15-00 kubectl=1.18.15-00.fusion-syntax-highlighter-98 > .CodeMirror, .fusion-syntax-highlighter-98 > .CodeMirror .CodeMirror-gutters {background-color:var(--awb-color1);}.fusion-syntax-highlighter-98 > .CodeMirror .CodeMirror-gutters { background-color: var(--awb-color2); }.fusion-syntax-highlighter-98 > .CodeMirror .CodeMirror-linenumber { color: var(--awb-color8); }Copy to ClipboardSyntax Highlighter$ sudo apt-mark hold kubelet kubeadm kubectl### 2b. Initialise kubeadm .fusion-syntax-highlighter-99 > .CodeMirror, .fusion-syntax-highlighter-99 > .CodeMirror .CodeMirror-gutters {background-color:var(--awb-color1);}.fusion-syntax-highlighter-99 > .CodeMirror .CodeMirror-gutters { background-color: var(--awb-color2); }.fusion-syntax-highlighter-99 > .CodeMirror .CodeMirror-linenumber { color: var(--awb-color8); }Copy to ClipboardSyntax Highlighter$ sudo kubeadm init --pod-network-cidr=10.244.0.0/16Your Kubernetes master has initialized successfully!

2c. To start using your cluster, you need to run the following command as a regular user:

.fusion-syntax-highlighter-100 > .CodeMirror, .fusion-syntax-highlighter-100 > .CodeMirror .CodeMirror-gutters {background-color:var(--awb-color1);}.fusion-syntax-highlighter-100 > .CodeMirror .CodeMirror-gutters { background-color: var(--awb-color2); }.fusion-syntax-highlighter-100 > .CodeMirror .CodeMirror-linenumber { color: var(--awb-color8); }Copy to ClipboardSyntax Highlighter$ mkdir -p $HOME/.kube.fusion-syntax-highlighter-101 > .CodeMirror, .fusion-syntax-highlighter-101 > .CodeMirror .CodeMirror-gutters {background-color:var(--awb-color1);}.fusion-syntax-highlighter-101 > .CodeMirror .CodeMirror-gutters { background-color: var(--awb-color2); }.fusion-syntax-highlighter-101 > .CodeMirror .CodeMirror-linenumber { color: var(--awb-color8); }Copy to ClipboardSyntax Highlighter$ sudo cp -i /etc/kubernetes/admin.conf $HOME/.kube/config.fusion-syntax-highlighter-102 > .CodeMirror, .fusion-syntax-highlighter-102 > .CodeMirror .CodeMirror-gutters {background-color:var(--awb-color1);}.fusion-syntax-highlighter-102 > .CodeMirror .CodeMirror-gutters { background-color: var(--awb-color2); }.fusion-syntax-highlighter-102 > .CodeMirror .CodeMirror-linenumber { color: var(--awb-color8); }Copy to ClipboardSyntax Highlighter$ sudo chown $(id -u):$(id -g) $HOME/.kube/configCopy the join command and make a note of it.

For example:

.fusion-syntax-highlighter-103 > .CodeMirror, .fusion-syntax-highlighter-103 > .CodeMirror .CodeMirror-gutters {background-color:var(--awb-color1);}.fusion-syntax-highlighter-103 > .CodeMirror .CodeMirror-gutters { background-color: var(--awb-color2); }.fusion-syntax-highlighter-103 > .CodeMirror .CodeMirror-linenumber { color: var(--awb-color8); }Copy to ClipboardSyntax Highlighter$ kubeadm join XX.X.X.XXX:6443 --token d3i30u.7p5xuyzkc5t2fm0x --discovery-token-ca-cert-hash sha256:4d3e70e50a8b3ecfacc64585942b93564c9af555ab90c576c59e63def90245ac

2d. Set up Flannel

.fusion-syntax-highlighter-104 > .CodeMirror, .fusion-syntax-highlighter-104 > .CodeMirror .CodeMirror-gutters {background-color:var(--awb-color1);}.fusion-syntax-highlighter-104 > .CodeMirror .CodeMirror-gutters { background-color: var(--awb-color2); }.fusion-syntax-highlighter-104 > .CodeMirror .CodeMirror-linenumber { color: var(--awb-color8); }Copy to ClipboardSyntax Highlighter$ sudo sysctl net.bridge.bridge-nf-call-iptables=1 .fusion-syntax-highlighter-105 > .CodeMirror, .fusion-syntax-highlighter-105 > .CodeMirror .CodeMirror-gutters {background-color:var(--awb-color1);}.fusion-syntax-highlighter-105 > .CodeMirror .CodeMirror-gutters { background-color: var(--awb-color2); }.fusion-syntax-highlighter-105 > .CodeMirror .CodeMirror-linenumber { color: var(--awb-color8); }Copy to ClipboardSyntax Highlighter$ sudo kubectl apply -f https://raw.githubusercontent.com/coreos/flannel/ 2140ac876ef134e0ed5af15c65e414cf26827915/Documentation/kube-flannel.yml

2e. Verify the creation of the master in the cluster.

$ kubectl get nodes NAME STATUS ROLES AGE VERSION ip-XX-X-X-XXX Ready master 3m53s v1.18.15

$ kubectl get pods --all-namespaces* NAMESPACE    NAME                                   READY STATUS  RESTART AGE kube-system  coredns-54ff9cd656-ww6sw               1/1   Running 0       4m2s kube-system  coredns-54ff9cd656-xlrdr               1/1   Running 0       4m2s kube-system  etcd-ip-XX-X-X-XXX                     1/1   Running 0       2m59s kube-system  kube-apiserver-ip-XX-X-X-XXX           1/1   Running 0       3m11s kube-system  kube-controller-manager-ip-XX-X-X-XXX  1/1   Running 0       3m15s kube-system  kube-flannel-ds-amd64-4rl8d            1/1   Running 0       45s kube-system  kube-proxy-jpp7w                       1/1   Running 0       4m2s kube-system  kube-scheduler-ip-XX-X-X-XXX           1/1   Running 0       3m23s

3. Kubernetes node set up****

3a. Login into node 1 and install kubelet, kubeadm and kubectl*** *

.fusion-syntax-highlighter-106 > .CodeMirror, .fusion-syntax-highlighter-106 > .CodeMirror .CodeMirror-gutters {background-color:var(--awb-color1);}.fusion-syntax-highlighter-106 > .CodeMirror .CodeMirror-gutters { background-color: var(--awb-color2); }.fusion-syntax-highlighter-106 > .CodeMirror .CodeMirror-linenumber { color: var(--awb-color8); }Copy to ClipboardSyntax Highlighter$ sudo apt-get update && sudo apt-get install -y apt-transport-https curl.fusion-syntax-highlighter-107 > .CodeMirror, .fusion-syntax-highlighter-107 > .CodeMirror .CodeMirror-gutters {background-color:var(--awb-color1);}.fusion-syntax-highlighter-107 > .CodeMirror .CodeMirror-gutters { background-color: var(--awb-color2); }.fusion-syntax-highlighter-107 > .CodeMirror .CodeMirror-linenumber { color: var(--awb-color8); }Copy to ClipboardSyntax Highlighter$ curl -s https://packages.cloud.google.com/apt/doc/apt-key.gpg | sudo apt-key add -.fusion-syntax-highlighter-108 > .CodeMirror, .fusion-syntax-highlighter-108 > .CodeMirror .CodeMirror-gutters {background-color:var(--awb-color1);}.fusion-syntax-highlighter-108 > .CodeMirror .CodeMirror-gutters { background-color: var(--awb-color2); }.fusion-syntax-highlighter-108 > .CodeMirror .CodeMirror-linenumber { color: var(--awb-color8); }Copy to ClipboardSyntax Highlighter$ cat .fusion-syntax-highlighter-109 > .CodeMirror, .fusion-syntax-highlighter-109 > .CodeMirror .CodeMirror-gutters {background-color:var(--awb-color1);}.fusion-syntax-highlighter-109 > .CodeMirror .CodeMirror-gutters { background-color: var(--awb-color2); }.fusion-syntax-highlighter-109 > .CodeMirror .CodeMirror-linenumber { color: var(--awb-color8); }Copy to ClipboardSyntax Highlighter$ sudo apt-get update.fusion-syntax-highlighter-110 > .CodeMirror, .fusion-syntax-highlighter-110 > .CodeMirror .CodeMirror-gutters {background-color:var(--awb-color1);}.fusion-syntax-highlighter-110 > .CodeMirror .CodeMirror-gutters { background-color: var(--awb-color2); }.fusion-syntax-highlighter-110 > .CodeMirror .CodeMirror-linenumber { color: var(--awb-color8); }Copy to ClipboardSyntax Highlighter$ sudo apt-get install -y --allow-change-held-packages kubelet=1.18.15-00 kubeadm=1.18.15-00 kubectl=1.18.15-00.fusion-syntax-highlighter-111 > .CodeMirror, .fusion-syntax-highlighter-111 > .CodeMirror .CodeMirror-gutters {background-color:var(--awb-color1);}.fusion-syntax-highlighter-111 > .CodeMirror .CodeMirror-gutters { background-color: var(--awb-color2); }.fusion-syntax-highlighter-111 > .CodeMirror .CodeMirror-linenumber { color: var(--awb-color8); }Copy to ClipboardSyntax Highlighter$ sudo apt-mark hold kubelet kubeadm kubectl

3b**. Join cluster from the command copied above in the master.*** ***

.fusion-syntax-highlighter-112 > .CodeMirror, .fusion-syntax-highlighter-112 > .CodeMirror .CodeMirror-gutters {background-color:var(--awb-color1);}.fusion-syntax-highlighter-112 > .CodeMirror .CodeMirror-gutters { background-color: var(--awb-color2); }.fusion-syntax-highlighter-112 > .CodeMirror .CodeMirror-linenumber { color: var(--awb-color8); }Copy to ClipboardSyntax Highlighter$ sudo kubeadm join XX.X.X.XXX:6443 --token d3i30u.7p5xuyzkc5t2fm0x --discovery-token-ca-cert-hash sha256:4d3e70e50a8b3ecfacc64585942b93564c9af555ab90c576c59e63def90245ac This node has joined the cluster:

Repeat the steps for node 2.

4. Verify creation of nodes in cluster.**

Login into master and verify the cluster

$ kubectl get nodes* * NAME            STATUS     ROLES    AGE    VERSION ip-XX-X-X-XXX   Ready        105m   v1.18.15 ip-XXX-X-X-XX   Ready      master   123m   v1.18.15 ip-XX-X-X-XX    Ready        111m   v1.18.15

4. Deploying the nginx with nodeport service**

Use the following yaml for deploying nginx with nodeport service to test the cluster

.fusion-syntax-highlighter-113 > .CodeMirror, .fusion-syntax-highlighter-113 > .CodeMirror .CodeMirror-gutters {background-color:var(--awb-color1);}.fusion-syntax-highlighter-113 > .CodeMirror .CodeMirror-gutters { background-color: var(--awb-color2); }.fusion-syntax-highlighter-113 > .CodeMirror .CodeMirror-linenumber { color: var(--awb-color8); }Copy to ClipboardSyntax HighlighterapiVersion: apps/v1 kind: Deployment metadata: name: nginx spec: selector: matchLabels: run: nginx replicas: 2 template: metadata: labels: run: nginx spec: containers: - name: nginx image: nginx ports: - containerPort: 80

apiVersion: v1 kind: Service metadata: name: nginx labels: run: nginx spec: type: NodePort ports:

  • port: 80 protocol: TCP selector: run: nginx### **4.*Test the deployment .fusion-syntax-highlighter-114 > .CodeMirror, .fusion-syntax-highlighter-114 > .CodeMirror .CodeMirror-gutters {background-color:var(--awb-color1);}.fusion-syntax-highlighter-114 > .CodeMirror .CodeMirror-gutters { background-color: var(--awb-color2); }.fusion-syntax-highlighter-114 > .CodeMirror .CodeMirror-linenumber { color: var(--awb-color8); }Copy to ClipboardSyntax Highlighter$ curl -vk master-node:nodeport.fusion-syntax-highlighter-115 > .CodeMirror, .fusion-syntax-highlighter-115 > .CodeMirror .CodeMirror-gutters {background-color:var(--awb-color1);}.fusion-syntax-highlighter-115 > .CodeMirror .CodeMirror-gutters { background-color: var(--awb-color2); }.fusion-syntax-highlighter-115 > .CodeMirror .CodeMirror-linenumber { color: var(--awb-color8); }Copy to ClipboardSyntax Highlighter$ curl -vk node01:nodeport.fusion-syntax-highlighter-116 > .CodeMirror, .fusion-syntax-highlighter-116 > .CodeMirror .CodeMirror-gutters {background-color:var(--awb-color1);}.fusion-syntax-highlighter-116 > .CodeMirror .CodeMirror-gutters { background-color: var(--awb-color2); }.fusion-syntax-highlighter-116 > .CodeMirror .CodeMirror-linenumber { color: var(--awb-color8); }Copy to ClipboardSyntax Highlighter$ curl -vk node02:nodeport### About The Author### A. NageshSR Cloud Dev-Ops Engineer | Cloud Control

Senior Cloud DevOps Engineer with more than five years of experience in supporting, automating, and optimizing deployments to hybrid cloud platforms using DevOps processes, CI/CD, containers and Kubernetes in both Production and Development environments

Kubernetes- * On Linked-In