How to Deploy a Redis Cluster in Kubernetes

Redis is a popular in-memory data structure store, often used as a database, cache, and message broker. Deploying a Redis cluster in Kubernetes can enhance its availability and scalability. In this article, we’ll guide you through the steps to deploy a Redis cluster using Kubernetes, specifically on Minikube.

Step 1: Create a Namespace

To keep our Redis deployment organized, we will create a dedicated namespace called my-redis. Run the following command:

kubectl create namespace my-redis

Step 2: Define the Redis Deployment

Next, we’ll create a redis-deployment.yaml file that includes a ConfigMap for Redis configuration, a StatefulSet for the Redis instances, and a Service to expose the Redis cluster.

Here’s the content for redis-deployment.yaml:

apiVersion: v1
kind: ConfigMap
metadata:
  name: redis-config
  namespace: my-redis  # Specify the namespace
data:
  redis.conf: |
    bind 0.0.0.0
    protected-mode no
    appendonly yes
---
apiVersion: apps/v1
kind: StatefulSet
metadata:
  name: redis
  namespace: my-redis  # Specify the namespace
spec:
  serviceName: "redis"
  replicas: 5
  selector:
    matchLabels:
      app: redis
  template:
    metadata:
      labels:
        app: redis
    spec:
      containers:
      - name: redis
        image: redis:5
        command: ["redis-server", "/etc/redis/redis.conf"]
        volumeMounts:
        - name: redis-config
          mountPath: /etc/redis
        ports:
        - containerPort: 6379
      volumes:
      - name: redis-config
        configMap:
          name: redis-config
---
apiVersion: v1
kind: Service
metadata:
  name: redis
  namespace: my-redis  # Specify the namespace
spec:
  type: NodePort  # Change to NodePort for external access
  ports:
  - port: 6379
    nodePort: 30000  # You can specify a port or let Kubernetes assign one
  selector:
    app: redis

Step 3: Apply the Deployment

Now, let’s apply the deployment configuration. Run the following command to create the resources defined in redis-deployment.yaml:

kubectl apply -f redis-deployment.yaml

Step 4: Verify the Deployment

To check the status of your Redis cluster, you can use the following commands:

kubectl get statefulsets -n my-redis
kubectl get pods -n my-redis
kubectl get services -n my-redis

These commands will show you the state of the StatefulSet, the individual Redis pods, and the service that exposes Redis.

Step 5: Accessing the Redis Cluster

To access the Redis cluster from outside the Minikube environment, you need to retrieve the Minikube IP. Use the following command:

minikube ip

Once you have the Minikube IP, you can connect to your Redis cluster using the redis-cli tool. Replace with the actual IP address you obtained:

redis-cli -h <minikube-ip> -p 30000

Conclusion

This setup allows for increased availability and scalability of your Redis instances. You can now leverage Redis for caching, session management, or as a message broker in your applications.