/deployment-guide - MongoDB Deployment Strategies

Get guidance on deploying MongoDB for different scenarios and requirements.

Description

Interactive deployment planning based on your use case, scale, and requirements.

Usage

/deployment-guide [scenario]

Deployment Scenarios

Development Environment

/deployment-guide development

Your Setup:
├── Local MongoDB Instance
├── MongoDB Atlas Free Tier
└── Docker Compose Stack

Recommended:
✅ MongoDB Atlas M0 (Free)
✅ Local mongod for testing
✅ Docker for consistency

Setup Steps:
1. Create MongoDB Atlas account
2. Create free cluster (AWS, GCP, or Azure)
3. Whitelist your IP
4. Get connection string
5. Connect from application

Time to Production: < 30 minutes

Single Server Deployment

/deployment-guide single-server

Your Setup:
├── Single MongoDB instance
├── Backup strategy
└── Basic monitoring

Recommended:
✅ MongoDB 6.0+ (enterprise grade)
✅ SSD storage (essential!)
✅ Data directory: /var/lib/mongodb
✅ Log directory: /var/log/mongodb

Configuration:
- maxPoolSize: 100
- oplogMinRetentionHours: 24
- slowms: 100 (log slow queries)

Backup Strategy:
- Daily incremental backups
- Weekly full backups
- Test restore monthly

Limitations:
❌ No high availability
❌ Single point of failure
❌ Limited scalability

Use Case: Small apps, testing, non-critical data

High Availability (Replica Set)

/deployment-guide high-availability

Your Setup:
├── Replica Set (3+ members)
├── Automatic failover
├── Read preference options
└── Backup from secondary

Architecture:
┌─────────────────┐
│ Primary         │ ← Reads & Writes
├─────────────────┤
│ Secondary-1     │ ← Reads only
├─────────────────┤
│ Secondary-2     │ ← Reads only
├─────────────────┤
│ Arbiter (opt.)  │ ← Voting only
└─────────────────┘

Configuration:
```yaml
replication:
  replSetName: rs0
storage:
  journal:
    enabled: true

Benefits: ✅ Automatic failover (< 30 seconds) ✅ Data redundancy ✅ Read scaling with secondary reads ✅ Zero downtime deployments ✅ Point-in-time recovery via oplog

Maintenance:

• Monitor replication lag
• Check oplog size (at least 24 hours)
• Regular backups
• Test failover quarterly

Use Case: Production systems, critical data

### Sharded Cluster

/deployment-guide sharded

Your Setup: ├── Config Servers (3) ├── Mongos Routers (2+) ├── Shard Servers (3+) └── Load balancer

Architecture: ┌─────────────────────────────┐ │ Application Load Balancer │ ├──────────┬──────────┬───────┤ │ Mongos-1 │ Mongos-2 │Mongos-│ ├──────────┼──────────┼───────┤ │ Config │ Config │Config │ │ Servers │ Servers │Server │ ├──────────┼──────────┼───────┤ │ Shard-1 │ Shard-2 │Shard- │ │ (RS) │ (RS) │(RS) │ └──────────┴──────────┴───────┘

Shard Key Design: 🔑 Critical decision!

• Cardinality: High (many unique values)
• Distribution: Evenly distributed writes
• Query patterns: Frequently queried together

Examples: ✅ userId (high cardinality, good distribution) ✅ email (unique, high cardinality) ❌ status (low cardinality - creates hotspots) ❌ boolean fields (terrible cardinality)

Setup:

1. Deploy config servers (replica set)
2. Deploy mongos routers
3. Deploy shard servers (replica sets)
4. Enable sharding on database
5. Shard collections with proper key

Use Case: TB+ of data, millions of operations/sec

### MongoDB Atlas (Cloud)

/deployment-guide atlas

Recommended for Most Users!

Tiers: M0 (Free)

• 512MB storage
• Shared resources
• Development only

M2/M5 (Shared)

• 2GB-10GB
• Shared instances
• Testing/staging

M10+ (Dedicated)

• Dedicated servers
• Production-grade
• Replica sets, sharding

Setup Steps:

1. Create Atlas account
2. Create organization
3. Create project
4. Create cluster
5. Configure backup
6. Set up network access
7. Get connection string

Features Included: ✅ Automatic backups ✅ High availability ✅ Encryption at rest ✅ Monitoring & alerting ✅ Automated patches ✅ 99.99% SLA

Pricing: Pay as you go

### Multi-Region Deployment

/deployment-guide multi-region

Your Setup: ├── Primary Region (US-East) ├── Secondary Region (EU-West) └── Read-only Region (Asia-Pacific)

Architecture: ┌──────────────────┐ │ US-East (Primary)│ │ - Replica Set │ │ - Writes here │ └────────┬─────────┘ │ Replication │ ┌────┴─────────────┐ │ │ ┌───▼────────┐ ┌─────▼───────┐ │EU-West(RO) │ │APAC (RO) │ │- Reads │ │- Reads │ └────────────┘ └─────────────┘

Benefits:
✅ Data locality (faster reads)
✅ Disaster recovery
✅ High availability across regions
✅ Regulatory compliance (GDPR)

Considerations:
⚠️ Replication lag (100-300ms typical)
⚠️ Higher costs
⚠️ Complexity in operations
⚠️ Eventual consistency

Setup:
1. Deploy primary replica set
2. Add secondary members in other regions
3. Configure firewall for replication
4. Monitor replication lag
5. Set read preferences per region

Pre-Deployment Checklist

Infrastructure
☐ SSD storage allocated
☐ Network configured
☐ Firewall rules set
☐ Backup storage prepared
☐ Monitoring tools installed

MongoDB Configuration
☐ Authentication enabled
☐ TLS/SSL configured
☐ Encryption at rest enabled
☐ Audit logging enabled
☐ Slow query logging configured

Testing
☐ Connection tested
☐ CRUD operations verified
☐ Failover tested (if replica set)
☐ Backup/restore tested
☐ Performance baseline established

Documentation
☐ Connection strings documented
☐ Backup procedures documented
☐ Disaster recovery plan
☐ Runbooks created
☐ Contact list updated

Scaling Decision Tree

How much data?
├─ < 1GB: Single server or Atlas M0
├─ 1-10GB: Single server with backups
├─ 10-100GB: Replica set
├─ 100GB-1TB: Replica set + optimization
├─ 1-10TB: Sharded cluster (2-3 shards)
└─ > 10TB: Sharded cluster (4+ shards)

How many operations/sec?
├─ < 1K: Single server
├─ 1K-10K: Replica set
├─ 10K-100K: Replica set + indexes
├─ 100K-1M: Sharded cluster
└─ > 1M: Large sharded cluster + optimization

Production Readiness Checklist

✅ High availability strategy (replica sets) ✅ Backup and recovery procedures ✅ Security (auth, encryption, audit) ✅ Monitoring and alerting ✅ Performance baseline and SLAs ✅ Disaster recovery plan ✅ Runbooks for common operations ✅ 24/7 operations support ✅ Regular testing of backups ✅ Capacity planning and growth strategy