How to Install Redis on Kubernetes?

This article will guide you through the process of installing Redis, a popular in-memory data structure store, on a Kubernetes (K8s) environment. Kubernetes, with its robust orchestration capabilities, is ideal for managing Redis instances that require high availability and quick scalability.

Before you begin, ensure you have a working Kubernetes cluster with kubectl installed and properly configured. This initial setup is crucial for successfully deploying and managing Redis within your Kubernetes infrastructure.

Prerequisites

A Kubernetes cluster up and running.
kubectl tool installed and configured to interact with your cluster.
Helm package manager installed on your local machine

Setting Up the Environment

Note: Kubernetes uses namespaces to organize and isolate cluster resources by team, application, or environment. In this guide, we will deploy Redis in its own namespace to keep it separate from other applications.

Step 1: Add the Helm Repository

Helm is a package manager for Kubernetes that simplifies the deployment and management of applications. The first step in installing Redis is to add the Bitnami repository, which contains a pre-configured Helm chart for Redis:

helm repo add bitnami https://charts.bitnami.com/bitnami

This command registers the Bitnami repository with Helm, making the Redis chart available for installation.

Step 2: Update the Helm Repository

After adding the new repository, update your Helm chart repository to ensure you have the latest list of charts and updates:

helm repo update

This command synchronizes your local Helm chart repository with the remote one, ensuring you have access to the latest charts provided by Bitnami.

Configuration

Prepare the `values.yaml` File

To customize the Redis deployment to your specific needs, you will need to create and modify a values.yaml file. This file contains configuration settings like resource limits and storage options. Here is an example values.yaml:

master:
  persistence:
    size: 2Gi
  resources:
    limits:
      memory: 2Gi
    requests:
      memory: 1Gi
replica:
  persistence:
    size: 5Gi
  replicaCount: 1
  resources:
    limits:
      memory: 2Gi
    requests:
      memory: 1Gi

This configuration defines the resource allocation and storage requirements for both the Redis master and replica instances. It ensures that Redis has enough memory and disk space to perform effectively while managing cost and resource usage within your cluster.

Installation

Create a Namespace for Redis

Before deploying Redis, create a dedicated namespace for it:

kubectl create namespace redis

This command creates a new namespace named redis, providing an isolated environment for running your Redis instances.

Install Redis Using Helm

Now, install Redis into the newly created namespace using the Helm chart:

helm upgrade --install redis bitnami/redis --values values.yaml --namespace redis --create-namespace

This command tells Helm to install the Redis chart from the Bitnami repository. If Redis is not already installed, Helm will install it (--install). The upgrade option allows you to update an existing installation or configure additional parameters without affecting existing data. It uses the configurations specified in values.yaml and deploys Redis in the redis namespace.

Wrap Up

After deployment, you can monitor the status of the Redis pods to ensure they are running correctly:

kubectl get pods -n redis

You should expect output similar to this, confirming that the Redis instances are up and operational:

Expected output

NAME                       READY   STATUS    RESTARTS   AGE
redis-master-0             1/1     Running   0          10m
redis-replica-0            1/1     Running   0          10m

By following these steps, you will have successfully deployed a scalable and robust Redis instance on your Kubernetes cluster, ready to handle your application's caching and data structure management needs effectively.