MongoDB Sharding

Introduction to MongoDB Sharding

MongoDB sharding enables horizontal scaling by distributing data across multiple machines. This guide covers sharding concepts, cluster configuration, and best practices for production deployments.

MongoDB Sharding

MongoDB Sharded Cluster Architecture

Sharding Components

Cluster Components

Mongos (Query Router)

Routes client requests to appropriate shards

Config Servers

Store metadata and configuration for the cluster

Shard Servers

Store the actual data in replica sets

Sharding Process

  • Chunk distribution
  • Balancing operations
  • Data migration
  • Split operations
  • Merge operations

Sharding Strategies

Shard Key Selection

# Enable sharding for database
sh.enableSharding("myDatabase")

# Shard collection with range-based shard key
sh.shardCollection("myDatabase.users", { "userId": 1 })

# Shard collection with hashed shard key
sh.shardCollection("myDatabase.logs", { "timestamp": "hashed" })

# Check sharding status
sh.status()

Sharding Types

  • Range-based sharding
  • Hashed sharding
  • Zoned sharding
  • Compound shard keys
  • Custom sharding

Cluster Management

Cluster Operations

Balancing

Automatic data distribution across shards

Chunk Migration

Moving chunks between shards for load balancing

Performance Monitoring

Tracking cluster performance and health

Maintenance Tasks

  • Adding/removing shards
  • Rebalancing data
  • Upgrading cluster
  • Backup and restore
  • Performance tuning

Monitoring & Maintenance

Health Checks

# Check cluster status
sh.status()

# Check balancer status
sh.getBalancerStatus()

# Check chunk distribution
sh.getChunks()

# Monitor cluster metrics
db.serverStatus().sharding

Performance Optimization

  • Chunk size tuning
  • Balancer configuration
  • Index optimization
  • Query optimization
  • Resource allocation

Best Practices

Configuration Guidelines

  • Proper shard key selection
  • Hardware requirements
  • Network configuration
  • Security setup
  • Monitoring strategy

Common Pitfalls

  • Poor shard key choice
  • Insufficient resources
  • Network bottlenecks
  • Inadequate monitoring
  • Improper maintenance

Next Steps

Now that you understand MongoDB sharding, you can explore:

MongoDB Tutorial