Deploy Redis on RamNode VPS | In-Memory Database Guide

Prerequisites & VPS Selection

Development

• 512MB RAM
• Learning & testing

Small Prod

• 1-2GB RAM
• Caching, sessions

Medium Prod

• 4-8GB RAM
• Larger datasets

Large Prod

• 16GB+ RAM
• High-traffic apps

View VPS Plans →

What You'll Need

Ubuntu 22.04/24.04 LTS or Debian 11/12
Root or sudo access
SSH access configured
Basic Linux command line familiarity

Install Redis

Install Redis from the official repository for the latest stable version:

Step 1: Update System Packages

sudo apt update
sudo apt upgrade -y

Step 2: Install Prerequisites

sudo apt install -y curl gnupg lsb-release

Step 3: Add Official Redis Repository

curl -fsSL https://packages.redis.io/gpg | sudo gpg --dearmor -o /usr/share/keyrings/redis-archive-keyring.gpg
echo "deb [signed-by=/usr/share/keyrings/redis-archive-keyring.gpg] https://packages.redis.io/deb $(lsb_release -cs) main" | sudo tee /etc/apt/sources.list.d/redis.list

Step 4: Install Redis

sudo apt update
sudo apt install -y redis

Step 5: Start and Enable Service

sudo systemctl start redis-server
sudo systemctl enable redis-server

Step 6: Verify Installation

redis-cli ping

✅ Success: You should see "PONG" as the response, indicating Redis is running correctly.

Configuration

Configure Redis in /etc/redis/redis.conf:

Open Configuration File

sudo nano /etc/redis/redis.conf

Key Configuration Options

Directive	Default	Description
bind	127.0.0.1	IP address(es) to listen on
port	6379	TCP port for connections
daemonize	yes	Run as background daemon
maxmemory	0	Maximum memory usage limit
maxmemory-policy	noeviction	Eviction policy when maxmemory reached
timeout	0	Client idle timeout (0 = disabled)

Memory Management

Set memory limits to prevent Redis from consuming all system RAM:

Memory Settings

# Set maximum memory (adjust based on your VPS)
maxmemory 256mb

# Eviction policy when maxmemory is reached
# Options: volatile-lru, allkeys-lru, volatile-random,
#          allkeys-random, volatile-ttl, noeviction
maxmemory-policy allkeys-lru

Eviction Policy Comparison

Policy	Description
volatile-lru	Evict least recently used keys with expiration set
allkeys-lru	Evict least recently used keys (recommended for caching)
volatile-ttl	Evict keys with shortest TTL first
noeviction	Return errors when memory limit reached

Security Hardening

Secure your Redis installation:

Password Authentication

Generate Strong Password

openssl rand -base64 32

Set Password in redis.conf

requirepass YourStrongPassword123!@#

Authenticate with CLI

redis-cli
AUTH YourStrongPassword123!@#

Network Security

Bind to Specific Interfaces

# Only accept local connections (most secure)
bind 127.0.0.1 ::1

# Accept connections from specific private IP
bind 127.0.0.1 10.0.0.5

Configure Firewall (UFW)

# Allow Redis from specific IP only
sudo ufw allow from 10.0.0.10 to any port 6379

# Or allow from subnet
sudo ufw allow from 10.0.0.0/24 to any port 6379

SSH Tunneling for Remote Access

# From client machine
ssh -L 6379:127.0.0.1:6379 user@your-ramnode-vps

TLS/SSL Encryption (Redis 6.0+)

Generate TLS Certificates

sudo mkdir -p /etc/redis/tls
cd /etc/redis/tls

sudo openssl genrsa -out redis.key 4096
sudo openssl req -new -key redis.key -out redis.csr -subj "/CN=redis"
sudo openssl x509 -req -days 365 -in redis.csr -signkey redis.key -out redis.crt

TLS Configuration in redis.conf

tls-port 6380
tls-cert-file /etc/redis/tls/redis.crt
tls-key-file /etc/redis/tls/redis.key
tls-auth-clients no

Disable Dangerous Commands

Rename/Disable Commands in redis.conf

# Rename dangerous commands
rename-command FLUSHDB ""
rename-command FLUSHALL ""
rename-command DEBUG ""
rename-command CONFIG "ADMIN_CONFIG_b4c2d8f1"

Data Persistence

Redis offers two persistence mechanisms to protect against data loss:

RDB Snapshots

Creates point-in-time snapshots at specified intervals:

RDB Configuration

# Save snapshot rules (seconds changes)
save 900 1        # Save if 1 key changed in 900 seconds
save 300 10       # Save if 10 keys changed in 300 seconds
save 60 10000     # Save if 10000 keys changed in 60 seconds

# Snapshot filename and directory
dbfilename dump.rdb
dir /var/lib/redis

Append-Only File (AOF)

Logs every write operation for better durability:

AOF Configuration

appendonly yes
appendfilename "appendonly.aof"

# Fsync policy options:
# - always: Most durable, slowest
# - everysec: Good balance (recommended)
# - no: Fastest, least durable
appendfsync everysec

Hybrid Persistence (Recommended)

Redis 4.0+ combines RDB and AOF benefits:

Enable Hybrid Persistence

aof-use-rdb-preamble yes

💡 This creates an AOF file that starts with an RDB snapshot followed by AOF commands for optimal recovery.

Basic Redis Commands

Connect to Redis

redis-cli
# Or with authentication:
redis-cli -a YourPassword

Essential Commands

Command	Description
SET key value	Store a string value
GET key	Retrieve a string value
DEL key	Delete a key
EXPIRE key seconds	Set expiration time
TTL key	Get remaining time to live
KEYS pattern	Find keys matching pattern
INFO	Server information and statistics
DBSIZE	Number of keys in database
MONITOR	Real-time command monitoring

Working with Data Types

Strings

SET user:1:name "John Doe"
GET user:1:name
INCR page:views

Hashes

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

Lists

LPUSH queue:tasks "task1"
RPUSH queue:tasks "task2"
LPOP queue:tasks
LRANGE queue:tasks 0 -1

Sets

SADD tags:post:1 "redis" "tutorial" "vps"
SMEMBERS tags:post:1
SISMEMBER tags:post:1 "redis"

Common Use Cases

Session Storage

Store user sessions with automatic expiration:

Session Management

# Store session with 30-minute expiration
SETEX session:abc123 1800 '{"user_id":1,"role":"admin"}'

# Retrieve session
GET session:abc123

# Extend session
EXPIRE session:abc123 1800

Application Caching

Cache database queries or API responses:

Caching Patterns

# Cache with 5-minute TTL
SETEX cache:user:1:profile 300 '{"name":"John","email":"john@example.com"}'

# Check if cached
EXISTS cache:user:1:profile

# Invalidate cache
DEL cache:user:1:profile

Rate Limiting

Implement API rate limiting:

Rate Limiting

# Increment request counter (resets every minute)
INCR ratelimit:api:192.168.1.1
EXPIRE ratelimit:api:192.168.1.1 60

# Check current count
GET ratelimit:api:192.168.1.1

Monitoring & Health Checks

Health Checks

# Basic connectivity check
redis-cli ping

# Detailed server information
redis-cli INFO

# Memory usage
redis-cli INFO memory

# Connected clients
redis-cli INFO clients

# Keyspace statistics
redis-cli INFO keyspace

Key Performance Metrics

Metric	What to Watch
used_memory	Should stay below maxmemory setting
connected_clients	Sudden spikes may indicate issues
blocked_clients	Should typically be 0
instantaneous_ops_per_sec	Operations throughput
hit_rate	Cache effectiveness (keyspace_hits / total)
rdb_last_bgsave_status	Should be "ok"

Backup Strategy

Automated Backup Script

#!/bin/bash
# /opt/scripts/redis-backup.sh

BACKUP_DIR=/var/backups/redis
DATE=$(date +%Y%m%d_%H%M%S)

# Trigger RDB save
redis-cli -a "YourPassword" BGSAVE

# Wait for save to complete
sleep 5

# Copy RDB file
cp /var/lib/redis/dump.rdb $BACKUP_DIR/dump_$DATE.rdb

# Keep only last 7 days
find $BACKUP_DIR -name "dump_*.rdb" -mtime +7 -delete

Schedule with Cron

# Make executable
chmod +x /opt/scripts/redis-backup.sh

# Daily backup at 2 AM
0 2 * * * /opt/scripts/redis-backup.sh

Troubleshooting

Common Issues & Solutions

Issue	Solution
Connection refused	Check if Redis is running: `systemctl status redis-server`
NOAUTH required	Provide password with -a flag or AUTH command
OOM (Out of Memory)	Increase maxmemory or adjust eviction policy
High latency	Check slow commands with `SLOWLOG GET 10`
Cannot connect remotely	Check bind settings and firewall rules
RDB save failing	Check disk space and permissions on data directory

View Logs

# View Redis logs
sudo tail -f /var/log/redis/redis-server.log

# Check for warnings
sudo grep -i warn /var/log/redis/redis-server.log

# Check service status
sudo systemctl status redis-server

Redis Deployed Successfully!

Your Redis installation is ready. Redis provides exceptional performance for caching, session management, and real-time data processing.

Next Steps:

✓ Regularly monitor your instance
✓ Maintain automated backups
✓ Keep Redis updated for security patches
✓ Consider Redis Sentinel for high availability
✓ Explore Redis Cluster for horizontal scaling

Additional Resources

Official Redis Documentation Redis Commands Reference Valkey Guide (Redis Alternative)RamNode Cloud VPS Documentation

Ready to Deploy Redis?

Get started with a RamNode VPS and deploy Redis in minutes. Our high-performance infrastructure is perfect for in-memory data workloads.

View VPS Plans →

Self-Hosted Redis

📋 Guide Contents

Prerequisites & VPS Selection

Development

Small Prod

Medium Prod

Large Prod

What You'll Need

Install Redis

Configuration

Key Configuration Options

Memory Management

Eviction Policy Comparison

Security Hardening

Password Authentication

Network Security

TLS/SSL Encryption (Redis 6.0+)

Disable Dangerous Commands

Data Persistence

RDB Snapshots

Append-Only File (AOF)

Hybrid Persistence (Recommended)

Basic Redis Commands

Essential Commands

Working with Data Types

Common Use Cases

Session Storage

Application Caching

Rate Limiting

Monitoring & Health Checks

Key Performance Metrics

Backup Strategy

Troubleshooting

Common Issues & Solutions

Redis Deployed Successfully!

Next Steps:

Additional Resources

Ready to Deploy Redis?

Self-Hosted Redis

Prerequisites & VPS Selection

Development

Small Prod

Medium Prod

Large Prod

What You'll Need

Install Redis

Alternative: Compile from Source

Configuration

Key Configuration Options

Memory Management

Eviction Policy Comparison

Security Hardening

Password Authentication

Network Security

TLS/SSL Encryption (Redis 6.0+)

Disable Dangerous Commands

Data Persistence

RDB Snapshots

Append-Only File (AOF)

Hybrid Persistence (Recommended)

Basic Redis Commands

Essential Commands

Working with Data Types

Common Use Cases

Session Storage

Application Caching

Rate Limiting

Monitoring & Health Checks

Key Performance Metrics

Backup Strategy

Troubleshooting

Common Issues & Solutions

Redis Deployed Successfully!

Next Steps:

Additional Resources

Ready to Deploy Redis?