Reviewed by Aditya Kumar · Last reviewed 2026-03-24
**CLI**: aws s3 cp, aws s3 sync. Sync is incremental. **boto3**: upload_file (handles multipart automatically for >8 MB), put_object for small. **S3 Transfer Acceleration**: Uses CloudFront edge for faster uploads from distant locations. **DataSync**: Agent-based for on-prem to...
CLI: aws s3 cp, aws s3 sync. Sync is incremental. boto3: upload_file (handles multipart automatically for >8 MB), put_object for small. S3 Transfer Acceleration: Uses CloudFront edge for faster uploads from distant locations. DataSync: Agent-based for on-prem to S3; handles large datasets, incremental. Snowball: Offline for very large (100+ TB); no network. Architectural choice: CLI for scripts; boto3 for apps; Transfer Acceleration when latency matters; DataSync for on-prem; Snowball for migration. Multipart: For single files >5 GB, multipart upload is required; upload_file does it. Best practice: Use multipart for large files; checksum for integrity; consider Transfer Acceleration for cross-region.
Pro-Move: 'We use boto3 upload_file with custom Config for 100MB+ chunks and checksum—reduced failed uploads and enabled resume.' Red Flag: Using put_object for 10GB file—will fail; need multipart.
According to DataEngPrep.tech, this is one of the most frequently asked Cloud/Tools interview questions, reported at 1 company. DataEngPrep.tech maintains an editor-reviewed database of 1,863 data engineering interview questions across 7 categories.