Setting Up a Kubernetes Cluster with Istio Service Mesh

In the ever-evolving world of container orchestration, efficiently managing Kubernetes clusters is crucial for seamless deployment and scalability. This guide focuses on setting up a brand new Kubernetes cluster and integrating the Istio service mesh for enhanced microservices communication.

Setting Up a Brand New Cluster

1. Update and Upgrade

Start by ensuring that your system is up-to-date by upgrading existing packages.

sudo apt update && sudo apt upgrade -y

2. Docker Reinstallation

Reinstall Docker with the latest version to ensure compatibility with the desired Kubernetes version.

sudo apt remove docker docker-engine docker.io containerd runc
sudo apt install docker.io

3. Initialize Kubernetes Cluster

Use kubeadm init to initialize the Kubernetes cluster, specifying the cluster CIDR for the Flannel CNI plugin.

sudo kubeadm init --pod-network-cidr=10.244.0.0/16

4. Addressing Network Allocation Issue

If you encounter the error "Error registering network: failed to acquire lease," edit the kube-controller-manager manifest file.

sudo nano /etc/kubernetes/manifests/kube-controller-manager.yaml

Add the following two args:

- --allocate-node-cidrs=true
- --cluster-cidr=10.244.0.0/16

5. Worker Node Join

On each worker node, upgrade packages, and join the cluster using the provided token.

sudo apt update && sudo apt upgrade -y
sudo kubeadm join --token <your-token> <master-node-ip>:<master-node-port>

6. Install CNI Plugin - Flannel (Helm)

Install the Flannel CNI plugin using Helm. Helm provides a convenient way to manage Kubernetes applications.

helm repo add flannel https://charts.flannel.io
helm repo update
helm install flannel flannel/flannel

7. Install Istio Service Mesh

Istio enhances microservices communication, providing features like load balancing, service discovery, and advanced routing. Use Istio's official Helm charts to install it.

helm repo add istio https://github.com/istio/istio/releases/download/<desired-istio-version>/istio-<desired-istio-version>
helm repo update

Install Istio's base components:

kubectl create namespace istio-system
helm install istio-base istio/istio-base -n istio-system

Install Istio's discovery components:

helm install istiod istio/istiod -n istio-system

8. Install Istio Ingress Gateway

Set up Istio's Ingress Gateway to manage external traffic to services within the cluster.

helm install istio-ingress istio/ingress -n istio-system

Now, you have a Kubernetes cluster set up with the Flannel CNI plugin and integrated with the Istio service mesh. This configuration provides a robust foundation for deploying and managing microservices, leveraging Istio's powerful features for improved service communication and control.