Data Migration to AWS: Tools and Best Practices

Planning Your AWS Data Migration Journey

Migrating data to AWS is a critical step in cloud adoption. Whether you’re moving databases, files, or entire applications, proper planning and the right tools ensure a smooth transition with minimal downtime.

Understanding AWS Migration Strategies: The 7 Rs

Rehost (Lift and Shift)

Move applications without modifications. Fastest approach but doesn’t leverage cloud-native benefits.

Replatform (Lift and Reshape)

Make minimal cloud optimizations during migration. Balance between speed and optimization.

Repurchase

Switch to cloud-native alternatives (SaaS). Replace legacy systems with AWS-managed services.

Refactor/Re-architect

Redesign applications to be cloud-native. Highest effort but maximum cloud benefits.

Retire

Decommission applications no longer needed. Reduces migration scope and costs.

Retain

Keep applications on-premises temporarily. Migrate later when ready.

Relocate

Move infrastructure to AWS without modifications (VMware Cloud on AWS).

AWS Data Migration Tools Overview

AWS offers a comprehensive suite of migration tools for different scenarios.

AWS Application Discovery Service

Discover on-premises infrastructure and application dependencies before migration. Provides insights into:

• Server specifications and utilization
• Network dependencies
• Application performance metrics
• Cost estimates for AWS

AWS Migration Hub

Central location to track migration progress across multiple AWS and partner tools. Provides unified view of migration status and automates progress tracking.

AWS Database Migration Service (DMS)

DMS helps migrate databases to AWS with minimal downtime.

Key Features of AWS DMS

• Supports homogeneous migrations (Oracle to Oracle)
• Supports heterogeneous migrations (Oracle to Aurora)
• Continuous data replication
• Minimal downtime during migration
• Automatic schema conversion with AWS SCT

Supported Database Sources

• Oracle, SQL Server, MySQL, PostgreSQL, MongoDB
• SAP ASE, IBM Db2
• Azure SQL Database
• Amazon RDS, Amazon Aurora, Amazon S3

DMS Migration Process

1. Create replication instance in AWS
2. Configure source and target endpoints
3. Create migration task with table mappings
4. Start migration and monitor progress
5. Perform validation and cutover

AWS Schema Conversion Tool (SCT)

AWS SCT converts database schemas and code objects when migrating between different database engines.

SCT Capabilities

• Automated schema conversion
• Application code conversion (SQL, stored procedures)
• Database assessment reports
• Compatibility analysis
• Optimization recommendations

Common Conversion Scenarios

• Oracle to Amazon Aurora PostgreSQL
• SQL Server to Amazon RDS for MySQL
• Teradata to Amazon Redshift
• Oracle to Amazon Redshift

AWS DataSync for File Transfers

AWS DataSync automates and accelerates moving data between on-premises storage and AWS.

DataSync Features

• Up to 10x faster than open-source tools
• Built-in data validation
• Bandwidth throttling
• Encryption in transit
• Support for NFS, SMB, HDFS, and S3

Use Cases for DataSync

• Data migration to AWS
• Ongoing data replication
• Archiving cold data to S3 Glacier
• Data processing workflows

AWS Snow Family for Large-Scale Data Transfer

When network transfer isn’t practical, AWS Snow devices provide physical data transport.

AWS Snowcone

• 8 TB of storage
• Portable and rugged
• Edge computing capabilities
• Ideal for remote locations

AWS Snowball

• 80 TB storage capacity
• Faster data transfer than internet
• Tamper-resistant and encrypted
• Good for datacenter migrations

AWS Snowmobile

• Up to 100 PB per Snowmobile
• Exabyte-scale data transfer
• For massive datacenter migrations
• Dedicated migration specialists

AWS Transfer Family for SFTP/FTPS/FTP

Managed file transfer service that enables SFTP, FTPS, and FTP access to Amazon S3 or EFS.

Transfer Family Benefits

• Fully managed service
• No infrastructure to maintain
• Integrates with existing authentication systems
• High availability and scalability
• Pay-per-use pricing

Database Migration Best Practices

Pre-Migration Assessment

• Analyze database size and complexity
• Identify dependencies and integrations
• Estimate migration timeline
• Calculate network bandwidth requirements

During Migration

• Use DMS test mode to validate
• Monitor replication lag
• Implement validation checks
• Maintain transaction logs

Post-Migration

• Verify data integrity
• Update connection strings
• Monitor application performance
• Optimize for cloud environment

Minimizing Downtime During Migration

Continuous Replication Strategy

1. Set up DMS with continuous replication
2. Perform initial full load
3. Maintain ongoing change data capture (CDC)
4. Run parallel testing on target database
5. Cut over during maintenance window

Multi-Phase Migration

• Migrate non-critical data first
• Test thoroughly before critical data
• Stagger migration to reduce risk
• Keep rollback plan ready

Data Migration Security Considerations

Encryption Requirements

• Encrypt data in transit using TLS/SSL
• Encrypt data at rest using AWS KMS
• Use VPN or AWS Direct Connect for sensitive data
• Implement IAM roles with least privilege

Compliance During Migration

• Maintain audit logs
• Ensure regulatory compliance (HIPAA, GDPR, PCI DSS)
• Data residency requirements
• Chain of custody documentation

Network Optimization for Data Transfer

Bandwidth Considerations

• Calculate required bandwidth: (Data Size / Available Time Window)
• Consider AWS Direct Connect for large transfers
• Use DataSync bandwidth throttling
• Schedule transfers during off-peak hours

Accelerating Transfers

• Use AWS DataSync acceleration
• Enable S3 Transfer Acceleration
• Compress data before transfer
• Parallelize transfers when possible

Post-Migration Optimization

Performance Tuning

• Right-size resources based on actual usage
• Implement caching strategies
• Optimize database queries
• Use CloudWatch for monitoring

Cost Optimization

• Analyze resource utilization
• Implement auto-scaling
• Use Reserved Instances or Savings Plans
• Archive infrequently accessed data to cheaper storage tiers

Common Migration Challenges and Solutions

Challenge: Large Data Volumes

Solution: Use AWS Snow devices or multi-stage migration with compression

Challenge: Minimal Downtime Requirements

Solution: Implement continuous replication with DMS and plan maintenance window cutover

Challenge: Complex Database Dependencies

Solution: Use Application Discovery Service and detailed dependency mapping

Challenge: Heterogeneous Database Migration

Solution: Use AWS SCT for schema conversion and extensive testing

Conclusion: Successful Data Migration Strategy

Successful AWS data migration requires careful planning, the right tools, and thorough testing. Start with a pilot migration, document lessons learned, and scale your approach for full production migration.