This comprehensive training covers data migration strategies from DataStax Enterprise (DSE) 5.1 to Hyper-Converged Database (HCD) with zero downtime. The training includes theoretical concepts, practical tools comparison, and hands-on lab exercises.

Official documentation relevant to this training can be found here: https://docs.datastax.com/en/data-migration

graph LR
    subgraph "Source"
        DSE[DSE 5.1/6.x<br/>Cassandra 3.x/4.x]
    end

    subgraph "Migration Approaches"
        direction TB
        HIST[Historical Data Migration]
        ZDM[Zero Downtime Migration]
        
        subgraph "Historical Options"
            NATIVE[Native Tools<br/>sstableloader, COPY]
            DSBULK[DSBulk<br/>Bulk Loader]
            CDM[CDM ⭐<br/>Spark-based]
        end
    end

    subgraph "Target"
        HCD[HCD<br/>Cassandra 4.1+]
    end

    subgraph "Application"
        APP[Your Application]
    end

    %% Historical migration paths
    DSE -->|Offline/Batch| NATIVE
    DSE -->|Offline/Batch| DSBULK
    DSE ==>|Recommended| CDM
    
    NATIVE -->|Load| HCD
    DSBULK -->|Import| HCD
    CDM ==>|Direct Transfer| HCD

    %% ZDM path
    APP -->|Phase 1| DSE
    APP -.->|Phase 2: Dual Write| ZDM
    ZDM -->|Primary| DSE
    ZDM -->|Secondary| HCD
    APP -.->|Phase 3| HCD

    %% Styling
    classDef source fill:#e1f5ff,stroke:#0066cc,stroke-width:2px
    classDef target fill:#e8f5e9,stroke:#2e7d32,stroke-width:2px
    classDef migration fill:#fff3e0,stroke:#f57c00,stroke-width:2px
    classDef recommended fill:#c8e6c9,stroke:#1b5e20,stroke-width:3px
    classDef app fill:#e0f2f1,stroke:#00695c,stroke-width:2px

    class DSE source
    class HCD target
    class NATIVE,DSBULK,HIST,ZDM migration
    class CDM recommended
    class APP app

Historical Data Migration (One-time bulk transfer)

• Native Tools: Basic sstableloader and COPY commands for small datasets
• DSBulk: DataStax Bulk Loader for medium-sized datasets with better performance
• CDM ⭐: Cassandra Data Migrator (Spark-based) - Recommended for production migrations

Zero Downtime Migration (Live traffic cutover)

• ZDM Proxy: Transparent proxy enabling dual-writes and gradual traffic cutover
• Supports phased migration: Direct → Proxy (dual-write) → Target

Typical Migration Flow:

1. Migrate historical data using CDM (offline/batch)
2. Deploy ZDM Proxy for new writes (dual-write mode)
3. Validate data consistency
4. Gradually cutover reads to target
5. Decommission source cluster

• docs/01-migration-overview.md - Migration fundamentals and planning
• docs/02-native-tooling.md - Native Cassandra/DSE tools
• docs/03-dse-tooling.md - DSE-specific migration tools
• docs/04-zdm-approach.md - Zero Downtime Migration proxy
• docs/05-cdm-approach.md - Cassandra Data Migrator
• docs/06-comparison-matrix.md - Tool comparison and decision guide
• docs/07-challenges-risks.md - Challenges, risks, and mitigation

• lab/README.md - Lab setup and exercises
• lab/docker-compose.yml - Lab environment configuration
• lab/exercises/ - Step-by-step lab exercises

• Docker Desktop or Colima installed
• Basic understanding of Cassandra/DSE architecture
• Familiarity with CQL (Cassandra Query Language)
• Command-line proficiency

# Start Colima with Rosetta 2 for full compatibility
colima start --arch aarch64 --vm-type=vz --vz-rosetta --cpu 6 --memory 12 --disk 60

# Navigate to lab directory
cd lab

# Start the lab environment
docker-compose up -d

# Verify containers are running
docker-compose ps

Note: Rosetta 2 is required for ZDM Proxy on Apple Silicon. See lab/ARM64-NOTES.md for details.

# Start Colima with sufficient resources
colima start --cpu 4 --memory 8 --disk 50

# Navigate to lab directory
cd lab

# Start the lab environment
docker-compose up -d

# Verify containers are running
docker-compose ps

# Navigate to lab directory
cd lab

# Start the lab environment
docker-compose up -d

# Verify containers are running
docker-compose ps

1. Read Documentation (2-3 hours)

   • Start with migration overview
   • Review each tooling approach
   • Study the comparison matrix
   • Understand challenges and risks

2. Complete Lab Exercises (3-4 hours)

   • Exercise 1: Environment setup and validation
   • Exercise 2: Native tooling migration
   • Exercise 3: ZDM proxy migration
   • Exercise 4: CDM migration
   • Exercise 5: Comparison and best practices

3. Review and Practice (1-2 hours)

   • Troubleshooting scenarios
   • Performance tuning
   • Production readiness checklist

By completing this training, you will:

• ✅ Understand Cassandra/DSE to HCD migration fundamentals
• ✅ Evaluate and select appropriate migration tools
• ✅ Implement zero-downtime migration strategies
• ✅ Identify and mitigate migration risks
• ✅ Handle common migration challenges
• ✅ Validate data consistency and integrity
• ✅ Optimize migration performance

• Documentation: See docs/ directory
• Lab Exercises: See lab/exercises/ directory
• Troubleshooting: See docs/08-troubleshooting.md

This training material is provided for educational purposes.