Multi Server

zAuctionHouse has been designed from the ground up with performance and scalability in mind. Whether you're running a small survival server or a large network like DonutSMP, zAuctionHouse is built to handle high traffic and multiple servers seamlessly.

zAuctionHouse Redis Addon

To connect multiple servers and synchronize your auction house across your entire network, you need the zAuctionHouse Redis addon.

Buy on GroupeZ - 15€Buy on BuiltByBit - 20.99$

Features

• Real-time synchronization - Items listed on one server appear instantly on all others
• Distributed locking - Prevents double purchases and race conditions
• Event propagation - All auction events (listing, purchase, removal) are synchronized
• Cache invalidation - Ensures all servers have up-to-date data
• High performance - Minimal latency impact on your servers

Why Redis?

Redis is an in-memory data structure store that provides extremely fast read and write operations. It is particularly well-suited for scenarios where multiple servers need to share and synchronize data in real time.

Performance Comparison

Solution	Speed	Real-time Sync	Data Consistency
Redis	Extremely fast (in-memory)	Yes	Excellent
SQL Database	Slower (disk-based)	No	Good
BungeeCord/Velocity	N/A	No	N/A

Why not SQL?

Unlike traditional SQL databases, which are disk-based and can introduce significant latency when handling frequent read and write operations, Redis operates directly in memory. This makes it ideal for applications that require high-performance, low-latency access to shared data.

Using SQL to synchronize multiple servers is not efficient for an auction house. SQL databases are designed for persistent storage, meaning each read or write operation involves disk access. This becomes a bottleneck when dealing with frequent updates from multiple servers. Additionally, SQL doesn't provide the real-time synchronization that an auction house requires, leading to delays and potential data conflicts.

info

zAuctionHouse still uses SQL (MySQL/MariaDB) for persistent data storage. Redis is used as a cache layer for real-time synchronization between servers.

Why not BungeeCord/Velocity messaging?

BungeeCord and Velocity are proxy solutions that facilitate communication between Minecraft servers, but they are not designed for data synchronization. While they can pass messages between servers, they lack the capability to efficiently manage shared data like auction items.

Redis, on the other hand, is designed for exactly this purpose: providing a shared, fast-access cache that multiple servers can use to ensure data consistency.

Key Benefits of Redis

1. In-memory storage - Data is stored in RAM for instant access
2. Pub/Sub messaging - Real-time event propagation across all servers
3. Atomic operations - Prevents race conditions and data corruption
4. Distributed locking - Ensures only one server can modify an item at a time
5. Scalability - Handles thousands of operations per second

Architecture

┌─────────────┐     ┌─────────────┐     ┌─────────────┐
│  Server 1   │     │  Server 2   │     │  Server 3   │
│zAuctionHouse│     │zAuctionHouse│     │zAuctionHouse│
│+ Redis Addon│     │+ Redis Addon│     │+ Redis Addon│
└──────┬──────┘     └──────┬──────┘     └──────┬──────┘
       │                   │                   │
       └───────────────────┼───────────────────┘
                           │
                    ┌──────▼──────┐
                    │    Redis    │
                    │   Server    │
                    └──────┬──────┘
                           │
                    ┌──────▼──────┐
                    │   MySQL /   │
                    │   MariaDB   │
                    └─────────────┘

How it works:

1. Player lists an item on Server 1
2. Item is saved to MySQL database
3. Redis publishes an event to all servers
4. Servers 2 and 3 receive the event and update their cache
5. Players on all servers see the item instantly

Installation

Requirements

• zAuctionHouse V4 on all servers
• Redis server (6.0+ recommended)
• MySQL/MariaDB database (shared between all servers)

Step 1: Install Redis

If you don't have a Redis server, you can install one:

Ubuntu/Debian:

sudo apt update
sudo apt install redis-server
sudo systemctl enable redis-server
sudo systemctl start redis-server

Docker:

docker run -d --name redis -p 6379:6379 redis:latest

Many hosting providers also offer managed Redis instances.

Step 2: Configure zAuctionHouse

Ensure all servers use the same MySQL database:

storage-type: 'MYSQL'
server-name: 'skyblock'
database-configuration:
  table-prefix: 'zauctionhouse_'
  host: '192.168.10.10'
  port: 3306
  user: 'homestead'
  password: 'secret'
  database: 'zauctionhouse'
  debug: false

Step 3: Install the Redis Addon

1. Download zAuctionHouseRedis from your purchase
2. Place zAuctionHouseRedis.jar in the plugins folder of each server
3. Start each server to generate the configuration

Step 4: Configure Redis Connection

Edit plugins/zAuctionHouseRedis/config.yml on each server:

redis-config:
  host: '192.168.10.10'
  port: 6379
  user: ''
  password: ''
  channel-name: 'zauctionhouse'
  database: 0
  timeout: 2000
  lock-ttl-seconds: 30
  pool:
    max-total: 64
    max-idle: 32
    min-idle: 16

Step 5: Restart Servers

Restart all servers. The plugin will automatically:

• Connect to your Redis server
• Subscribe to auction events
• Synchronize data between servers

Verification

To verify the addon is working:

1. Check the console for successful Redis connection message
2. List an item on Server 1
3. Open /ah on Server 2 - the item should appear immediately
4. Purchase the item on Server 2
5. Check Server 1 - the item should be removed from the listing

Troubleshooting

Cannot connect to Redis

• Verify Redis is running: redis-cli ping should return PONG
• Check host and port in configuration
• Ensure firewall allows connections on port 6379
• If using password authentication, verify the password is correct

Items not synchronizing

• Ensure all servers use the same MySQL database
• Verify Redis addon is installed on all servers
• Check console for any error messages
• Ensure all servers can connect to Redis

High latency

• Consider using a Redis server in the same datacenter as your game servers
• Check Redis server resources (CPU, memory)
• Review connection pool settings

Performance Tips

1. Use a local Redis server - Keep Redis in the same datacenter as your servers
2. Tune connection pool - Adjust pool settings based on your server load
3. Monitor Redis - Use redis-cli INFO to monitor performance
4. Enable persistence - Configure Redis RDB/AOF for data safety (optional)

Support

Need help setting up multi-server? Join our Discord server for support.