AWS DataSync - Complete Guide for AWS Solutions Architect Professional
Why AWS DataSync is Important
AWS DataSync is a critical service for organizations undergoing cloud migration and modernization initiatives. It addresses one of the most challenging aspects of cloud adoption: moving large volumes of data efficiently and securely. Understanding DataSync is essential for the Solutions Architect Professional exam because it frequently appears in scenarios involving hybrid architectures, data migration strategies, and workload modernization.
What is AWS DataSync?
AWS DataSync is a fully managed data transfer service that simplifies, automates, and accelerates moving data between on-premises storage systems and AWS storage services, as well as between AWS storage services themselves. It can transfer data up to 10 times faster than open-source tools by using a purpose-built network protocol and parallel transfer architecture.
Key Features:
• Automated data transfer with scheduling capabilities
• Built-in data integrity validation
• Encryption in transit and at rest
• Bandwidth throttling to control network usage
• Incremental transfers (only changed data)
• Metadata preservation (permissions, timestamps, etc.)
Supported Source and Destination Locations:
• On-premises: NFS, SMB file servers, HDFS, self-managed object storage
• AWS: Amazon S3 (all storage classes), Amazon EFS, Amazon FSx (Windows File Server, Lustre, OpenZFS, NetApp ONTAP)
• Other clouds: Google Cloud Storage, Azure Files, Azure Blob Storage
How AWS DataSync Works
1. Agent Deployment (for on-premises transfers):
A DataSync agent is deployed as a virtual machine in your on-premises environment or EC2 instance. The agent connects to your source storage and communicates with the DataSync service over TLS.
2. Location Configuration:
You define source and destination locations. For on-premises sources, the agent is associated with the location. For AWS-to-AWS transfers, no agent is required.
3. Task Creation:
Tasks define the transfer parameters including:
• Source and destination locations
• Transfer options (verify data, preserve metadata)
• Filtering options (include/exclude patterns)
• Scheduling configuration
• Bandwidth limits
4. Task Execution:
When a task runs, DataSync:
• Scans source and destination for differences
• Transfers only changed or new files
• Validates data integrity using checksums
• Reports detailed transfer statistics
Architecture Considerations:
• Each agent supports up to 4 tasks running concurrently
• Agents require outbound connectivity on port 443
• For high-bandwidth transfers, multiple agents can be deployed
• VPC endpoints can be used for private connectivity
Common Use Cases
Data Migration: One-time or ongoing migration of file data to AWS storage services
Data Protection: Replicating data to AWS for backup and disaster recovery
Cold Data Archival: Moving infrequently accessed data to S3 Glacier storage classes
Hybrid Workflows: Synchronizing data between on-premises and cloud for processing
Cross-Region/Cross-Account Transfers: Moving data between AWS regions or accounts
Exam Tips: Answering Questions on AWS DataSync
Scenario Recognition:
• Look for keywords like migrate large datasets, transfer files to S3/EFS/FSx, NFS or SMB migration, data synchronization
• When the question mentions preserving file metadata, permissions, or timestamps, DataSync is likely the answer
• Questions involving scheduled, recurring transfers often point to DataSync
DataSync vs. Other Services:
DataSync vs. Storage Gateway:
• DataSync = data transfer and migration (move data)
• Storage Gateway = hybrid storage integration (extend storage to cloud)
• If the question asks about ongoing hybrid access with local caching, choose Storage Gateway
• If the question asks about migrating data to AWS, choose DataSync
DataSync vs. S3 Transfer Acceleration:
• DataSync = file system to AWS storage transfers
• S3 Transfer Acceleration = faster uploads to S3 over public internet
• DataSync supports multiple destination types; Transfer Acceleration is S3-only
DataSync vs. AWS Transfer Family:
• DataSync = bulk data transfers, scheduled migrations
• Transfer Family = SFTP/FTPS/FTP protocol access to S3/EFS
• If the question mentions existing SFTP workflows or B2B file transfers, choose Transfer Family
DataSync vs. Snowball:
• DataSync = network-based transfer, suitable when bandwidth allows
• Snowball = physical device, suitable for limited bandwidth or massive datasets (petabytes)
• Calculate transfer time: if network transfer takes weeks/months, Snowball might be better
Key Points for Exam Success:
1. Agent Requirements: Agents are needed for on-premises to AWS transfers but NOT for AWS-to-AWS transfers
2. Bandwidth Control: DataSync can throttle bandwidth to avoid impacting production workloads
3. Incremental Transfers: Only changed data is transferred after initial sync, making it efficient for ongoing synchronization
4. Data Validation: DataSync performs automatic integrity checks using checksums
5. VPC Endpoints: For private connectivity that avoids the public internet, use VPC endpoints with DataSync
6. Cross-Account Transfers: DataSync supports transferring data between different AWS accounts
7. Scheduling: Tasks can be scheduled for specific times or run on demand
Common Exam Traps to Avoid:
• Do not confuse DataSync with Database Migration Service (DMS) - DataSync is for file/object data, DMS is for databases
• Remember that DataSync preserves metadata while S3 CLI sync commands may not preserve all attributes
• DataSync is not appropriate for real-time replication; it is designed for batch transfers
• When questions mention minimal operational overhead for data transfers, DataSync is typically preferred over custom scripts or open-source tools
Performance Optimization Tips:
• Use multiple agents for higher throughput requirements
• Enable compression for WAN transfers
• Use task filtering to exclude unnecessary files
• Schedule transfers during off-peak hours to maximize available bandwidth