Installing Redis

Introduction

Before you can use Redis, you need to install the server and the CLI client. Redis runs natively on Linux and macOS, and Docker provides a consistent experience on any platform including Windows.

Key Concepts

• redis-server: The Redis server process that stores data and processes commands.
• redis-cli: The command-line interface for connecting to and interacting with a Redis server.
• Port 6379: The default TCP port Redis listens on.
• redis.conf: The configuration file controlling Redis behavior (memory limits, persistence, networking).

Real World Context

In development, you typically run Redis locally via Homebrew or Docker. In production, Redis is deployed as a managed service (AWS ElastiCache, Redis Cloud) or as a containerized service in Kubernetes. Understanding local installation helps you debug and test before deploying.

Deep Dive

Let's get Redis running on your system. Redis runs natively on Linux and macOS. For Windows, we recommend using Docker or WSL2.

macOS Installation (Homebrew)

The easiest way to install Redis on macOS:

bash
# Install Redis
brew install redis

# Start Redis as a background service
brew services start redis

# Or start it manually
redis-server

# Verify installation
redis-cli ping
# Should return: PONG

Linux Installation (Ubuntu/Debian)

bash
# Update package lists
sudo apt update

# Install Redis
sudo apt install redis-server

# Start and enable the service
sudo systemctl start redis-server
sudo systemctl enable redis-server

# Verify it's running
redis-cli ping
# Should return: PONG

Docker Installation (All Platforms)

Docker provides the most consistent experience across platforms:

bash
# Pull and run Redis
docker run --name my-redis -p 6379:6379 -d redis

# Connect to it
docker exec -it my-redis redis-cli

Connecting with redis-cli

The redis-cli is the command-line interface for Redis:

bash
# Connect to local Redis (default port 6379)
redis-cli

# Connect to specific host and port
redis-cli -h localhost -p 6379

# Test the connection
127.0.0.1:6379> PING
PONG

Your First Commands

Once connected, try these basic commands:

redis
# Store a value
127.0.0.1:6379> SET greeting "Hello, Redis!"
OK

# Retrieve it
127.0.0.1:6379> GET greeting
"Hello, Redis!"

# Delete it
127.0.0.1:6379> DEL greeting
(integer) 1

# Check if it exists
127.0.0.1:6379> EXISTS greeting
(integer) 0

Configuration Basics

Redis configuration file location:

• macOS (Homebrew): /opt/homebrew/etc/redis.conf
• Linux: /etc/redis/redis.conf

Key settings to know:

# Network
bind 127.0.0.1          # Only accept local connections
port 6379               # Default port

# Memory
maxmemory 100mb         # Memory limit
maxmemory-policy allkeys-lru  # Eviction policy

# Persistence
save 900 1              # Save after 900 seconds if 1 key changed
appendonly yes          # Enable AOF persistence

📖 Redis Installation Guide

Common Pitfalls

1. Exposing Redis to the internet without authentication — By default Redis binds to localhost with no password. Never expose port 6379 publicly without setting a password and firewall rules.
2. Forgetting to start the service — After installation, Redis doesn't always auto-start. Use brew services start redis or systemctl enable redis-server to ensure it starts on boot.

Best Practices

1. Use Docker for consistent environments — Docker ensures the same Redis version across development, CI, and staging.
2. Verify with PING — After installation, always run redis-cli ping to confirm connectivity before proceeding.

Summary

• Install Redis via Homebrew (macOS), apt (Linux), or Docker (any platform).
• The default port is 6379 and the CLI tool is redis-cli.
• Always verify installation with redis-cli ping (should return PONG).
• Configuration lives in redis.conf — key settings include bind, port, maxmemory, and persistence.

# Install with Homebrew (macOS)
brew install redis
brew services start redis

# Or with Docker (any platform)
docker run --name my-redis -p 6379:6379 -d redis

# Verify connection
redis-cli ping
# Returns: PONG