EZ-Homelab/wiki/service-docs/redis.md

Redis - In-Memory Cache

Table of Contents

• Overview
• What is Redis?
• Why Use Redis?
• Configuration in AI-Homelab
• Official Resources
• Redis Instances

Overview

Category: In-Memory Data Store
Docker Image: redis
Default Stack: development.yml and others
Ports: 6379 (internal)

What is Redis?

Redis (Remote Dictionary Server) is an in-memory data structure store used as a cache, message broker, and database. It's incredibly fast because data is stored in RAM, making it perfect for caching, sessions, queues, and real-time applications.

Key Features

• In-Memory: Microsecond latency
• Data Structures: Strings, lists, sets, hashes, etc.
• Persistence: Optional disk writes
• Pub/Sub: Message broker
• Atomic Operations: Thread-safe operations
• Replication: Master-slave
• Lua Scripting: Server-side scripts
• Free & Open Source: BSD license

Why Use Redis?

1. Speed: Extremely fast (in RAM)
2. Versatile: Cache, queue, pub/sub, database
3. Simple: Easy to use
4. Reliable: Battle-tested
5. Rich Data Types: More than key-value
6. Atomic: Safe concurrent access
7. Popular: Wide adoption

Configuration in AI-Homelab

AI-Homelab uses Redis for caching and session storage in multiple applications.

Official Resources

• Website: https://redis.io
• Documentation: https://redis.io/docs
• Commands: https://redis.io/commands

Redis Instances

Authentik Redis (authentik-redis)

authentik-redis:
  image: redis:alpine
  container_name: authentik-redis
  restart: unless-stopped
  networks:
    - traefik-network
  command: --save 60 1 --loglevel warning
  volumes:
    - /opt/stacks/infrastructure/authentik-redis/data:/data

Purpose: Authentik SSO caching and sessions
Location: /opt/stacks/infrastructure/authentik-redis/data

GitLab Redis (gitlab-redis)

gitlab-redis:
  image: redis:alpine
  container_name: gitlab-redis
  restart: unless-stopped
  networks:
    - traefik-network
  command: --save 60 1 --loglevel warning
  volumes:
    - /opt/stacks/development/gitlab-redis/data:/data

Purpose: GitLab caching and background jobs
Location: /opt/stacks/development/gitlab-redis/data

Development Redis (redis)

redis:
  image: redis:alpine
  container_name: redis
  restart: unless-stopped
  networks:
    - traefik-network
  ports:
    - "6379:6379"
  command: redis-server --appendonly yes --requirepass ${REDIS_PASSWORD}
  volumes:
    - /opt/stacks/development/redis/data:/data

Purpose: General development caching
Location: /opt/stacks/development/redis/data

Management

Access Redis CLI

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

# With password
docker exec -it redis redis-cli -a your_password

# Or authenticate after connecting
AUTH your_password

Common Commands

# Set key
SET mykey "Hello"

# Get key
GET mykey

# Set with expiration (seconds)
SETEX mykey 60 "expires in 60 seconds"

# List all keys
KEYS *

# Delete key
DEL mykey

# Check if key exists
EXISTS mykey

# Get key type
TYPE mykey

# Flush all data (careful!)
FLUSHALL

# Get info
INFO

Monitor Activity

# Monitor commands in real-time
docker exec -it redis redis-cli MONITOR

# Get statistics
docker exec -it redis redis-cli INFO stats

Backup Redis

# Redis automatically saves to dump.rdb
# Just backup the data volume
tar -czf redis-backup.tar.gz /opt/stacks/development/redis/data/

# Force save now
docker exec redis redis-cli SAVE

Summary

Redis provides in-memory storage offering:

• Ultra-fast caching
• Session storage
• Message queuing (pub/sub)
• Real-time operations
• Rich data structures
• Persistence options
• Atomic operations
• Free and open-source

Perfect for:

• Application caching
• Session storage
• Real-time analytics
• Message queues
• Leaderboards
• Rate limiting
• Pub/sub messaging

Key Points:

• In-memory (very fast)
• Data persists to disk optionally
• Multiple data structures
• Simple key-value interface
• Use password protection
• Low resource usage
• Alpine image is tiny

Remember:

• Set password (--requirepass)
• Data stored in RAM
• Configure persistence
• Monitor memory usage
• Backup dump.rdb file
• Use for temporary data
• Not a full database replacement

Redis accelerates your applications with caching!