Kubernetes Cluster with Rancher

I’ve created a blog post that demonstrates how to set up Rancher and integrate an existing AWS EKS cluster into it. Rancher is an open-source software platform that is used for managing the Kubernetes clusters.

Prerequisites

1. AWS EC2 Instance — Ubuntu
2. EKS cluster with kubectl access

Step 1: Install Docker on EC2 instance (Rancher Server)

I used to follow the below steps to install the latest Docker version in Ubuntu,

sudo apt-get update
sudo apt-get install \
    ca-certificates \
    curl \
    gnupg \
    lsb-release
sudo mkdir -p /etc/apt/keyrings
curl -fsSL https://download.docker.com/linux/ubuntu/gpg | sudo gpg --dearmor -o /etc/apt/keyrings/docker.gpg
echo \ "deb [arch=$(dpkg --print-architecture) signed-by=/etc/apt/keyrings/docker.gpg] https://download.docker.com/linux/ubuntu \ $(lsb_release -cs) stable" | sudo tee /etc/apt/sources.list.d/docker.list > /dev/null
sudo apt-get update
sudo apt-get install docker-ce docker-ce-cli containerd.io docker-compose-plugin

Step 2: Run the Latest Rancher image in Docker

sudo docker run -d --restart=always -p 80:80 -p 443:443 -v /opt/rancher:/var/lib/rancher --privileged rancher/rancher:latest

Step 3: Setup the Application Load Balancer

• Configure the ALB and Target group

• Point domain to ALB endpoint in Route 53

Step 4: Access Rancher URL in browser

Step 5: Login Rancher

• Follow the instructions that appear on the welcome page

• Login Rancher

Step 6: Add EKS cluster to Rancher

• Click on clusters and choose Generic

• Add the Cluster name and click on Create

Step 7: Apply the kubectl command

$ kubectl apply -f https://domain/v3/import/xxxxxxxxxx.yaml clusterrole.rbac.authorization.k8s.io/proxy-clusterrole-kubeapiserver created clusterrolebinding.rbac.authorization.k8s.io/proxy-role-binding-kubernetes-master created namespace/cattle-system created serviceaccount/cattle created clusterrolebinding.rbac.authorization.k8s.io/cattle-admin-binding created secret/cattle-credentials-3486dd8 created clusterrole.rbac.authorization.k8s.io/cattle-admin created deployment.apps/cattle-cluster-agent configured service/cattle-cluster-agent created
$ kubectl get all -n cattle-system
NAME                                        READY   STATUS    RESTARTS   AGE
pod/cattle-cluster-agent-68cb8c4784-mzfgc   1/1     Running   0          2m14s
pod/cattle-cluster-agent-68cb8c4784-xkg7r   1/1     Running   0          2m15s
NAME                           TYPE        CLUSTER-IP       EXTERNAL-IP   PORT(S)          AGE
service/cattle-cluster-agent   ClusterIP   172.20.125.115   <none>        80/TCP,443/TCP   52d
NAME                                   READY   UP-TO-DATE   AVAILABLE   AGE
deployment.apps/cattle-cluster-agent   2/2     2            2           52d
NAME                                              DESIRED   CURRENT   READY   AGE
replicaset.apps/cattle-cluster-agent-65bcff69d    0         0         0       52d
replicaset.apps/cattle-cluster-agent-68cb8c4784   2         2         2       2m15s
replicaset.apps/cattle-cluster-agent-68fb87d757   0         0         0       52d
replicaset.apps/cattle-cluster-agent-745894d768   0         0         0       2m55s

Step 8: Access the Rancher UI

• Once that is done, cluster metrics will show as below. You will be able to manage the EKS cluster now by creating new deployments, services, etc.

Summary

We can add an existing Kubernetes cluster or create a new Kubernetes cluster using Rancher and scale up and scale down multiple nodes, pods, etc.

Author

Created by @sebinxavi — feel free to contact me and advise as necessary!!

Originally published at https://github.com.