Redis

Configure Redis for caching and data storage.

Installation & Setup

# Install
apt install redis-server

# Configuration
# /etc/redis/redis.conf
bind 0.0.0.0
protected-mode yes
requirepass yourpassword
maxmemory 256mb
maxmemory-policy allkeys-lru

Basic Operations

redis-cli -a yourpassword

# String operations
SET key "value"
GET key
SETEX key 3600 "value"  # With TTL

# Hash
HSET user:1 name "John" email "john@example.com"
HGETALL user:1

# List
LPUSH queue "task1"
RPOP queue

Persistence

# RDB (snapshot)
save 900 1
save 300 10

# AOF (append-only file)
appendonly yes
appendfsync everysec

Sentinel (HA)

# sentinel.conf
sentinel monitor mymaster 10.0.0.1 6379 2
sentinel down-after-milliseconds mymaster 30000
sentinel failover-timeout mymaster 180000

Best Practices

• Set maxmemory and eviction policy
• Use persistence for critical data
• Implement Sentinel for HA
• Monitor memory usage