🚀 AWS ElastiCache (Redis) Setup Guide with EC2 Client

📌 Overview

This guide walks you through:

• Creating a Redis cluster using AWS ElastiCache
• Configuring networking (VPC, Subnets, Security Groups)
• Launching an EC2 instance
• Installing Redis CLI
• Connecting EC2 → ElastiCache Redis

🏗️ Architecture

EC2 (Client)
   ↓
Security Group (Port 6379)
   ↓
ElastiCache Redis Cluster (Primary + Replica)

⚙️ PHASE 1: Create ElastiCache Redis Cluster

🔹 Step 1: Go to ElastiCache

• Open AWS Console
• Search for ElastiCache
• Click Create Redis Cluster

🔹 Step 2: Choose Configuration

• Cluster Mode → Disabled (Node-based)
• Cluster Type → Cluster Cache
• Engine → Redis
• Version → Latest stable

🔹 Step 3: Cluster Settings

• Cluster Name → my-redis-cluster
• Node Type → cache.t3.micro (free-tier friendly)
• Number of Replicas → 1
• Multi-AZ → ❌ Disabled (for learning; enable in production)

🔹 Step 4: Connectivity Settings

• VPC → Default VPC
• Subnet Group → Create new

Create Subnet Group:

• Select 2 subnets only
• Choose different Availability Zones (AZs)

🔹 Step 5: Availability Zone Placement

• Choose: Specify Availability Zones
• Select 2 AZs manually

🔹 Step 6: Security & Encryption

• Encryption in Transit → ❌ Disabled (for simplicity)
• Encryption at Rest → Optional
• AUTH → Disabled (enable in production)

🔹 Step 7: Backup & Logging

• Backup → ❌ Disabled
• Log Delivery → ✅ Enabled (recommended)

🔹 Step 8: Create Cluster

• Click Create
• Wait ~5–10 minutes

🔐 PHASE 2: Configure Security Group

🔹 Step 1: Create Security Group

Go to EC2 → Security Groups → Create

• Name → redis-sg

Inbound Rules:

👉 Important: Allow only EC2 SG, NOT 0.0.0.0/0

🔹 Step 2: Attach SG to Redis

• Go to ElastiCache cluster
• Modify → Attach redis-sg

🖥️ PHASE 3: Launch EC2 Instance

🔹 Step 1: Create EC2

• AMI → Amazon Linux 2023

• Instance Type → t2.micro / t3.micro

• VPC → Same as Redis

• Security Group:

  • Allow SSH (22) from your IP

🔹 Step 2: Connect to EC2

ssh -i your-key.pem ec2-user@your-public-ip

🧰 PHASE 4: Install Redis CLI on EC2

🔹 Step 1: Check OS

cat /etc/os-release

🔹 Step 2: Update System

sudo dnf update -y

🔹 Step 3: Install Dependencies

sudo dnf install -y gcc gcc-c++ make jemalloc-devel openssl-devel tcl tcl-devel wget tar

🔹 Step 4: Download Redis

cd /tmp
wget http://download.redis.io/redis-stable.tar.gz

🔹 Step 5: Extract

tar xvzf redis-stable.tar.gz
cd redis-stable

🔹 Step 6: Build Redis (with TLS)

make BUILD_TLS=yes

🔹 Step 7: Install

sudo make install

🔹 Step 8: Verify Installation

redis-cli --version

🔌 PHASE 5: Connect EC2 to Redis

🔹 Step 1: Get Primary Endpoint

• Go to ElastiCache
• Copy Primary Endpoint

Example:

my-redis.xxxxxx.ng.0001.use1.cache.amazonaws.com:6379

🔹 Step 2: DNS Check

nslookup your-endpoint-without-port

🔹 Step 3: Connect to Redis

Without TLS:

redis-cli -h your-endpoint -p 6379

With TLS:

redis-cli -h your-endpoint --tls

🔹 Step 4: Test Connection

set name "AWS Redis"
get name

🔗 PHASE 6: Connect Application (Node.js)

Install Redis Client

npm install redis

Example Code

import { createClient } from "redis";

const client = createClient({
  socket: {
    host: "your-endpoint",
    port: 6379,
  },
});

await client.connect();

await client.set("key", "value");
const data = await client.get("key");

console.log(data);

Check:

✅ Same VPC ✅ Correct Security Group (Port 6379) ✅ EC2 allowed in Redis SG ✅ Endpoint copied correctly (no port in DNS step)

🎯 Final Flow

EC2 → Redis CLI → ElastiCache Primary Endpoint → Redis Cluster