How to Transfer Objects Between Two S3 Buckets Using AWS CLI

Amazon Web Services (AWS) provides the AWS Command Line Interface (CLI) to manage and automate various cloud operations. One common use case is transferring objects between two Amazon Simple Storage Service (S3) buckets. This guide will explain how to move objects efficiently using AWS CLI.

Prerequisites

Before transferring objects between S3 buckets, ensure the following prerequisites are met:

  1. AWS CLI Installed – Download and install the AWS CLI from the official AWS website.
  2. AWS Credentials Configured – Use the aws configure command to set up the necessary credentials.
  3. S3 Bucket Permissions – Ensure the necessary IAM roles and permissions allow read/write access to both S3 buckets.

Steps to Move Objects Between S3 Buckets

1. Verify AWS CLI Configuration

Run the following command to check the configured AWS credentials:

aws configure list

Ensure the AWS access key, secret key, and default region are correctly set.

2. List Objects in the Source Bucket

To confirm the files to be transferred, list all objects in the source bucket:

aws s3 ls s3://source-bucket-name –recursive

Replace source-bucket-name with the actual name of the S3 bucket.

3. Copy Objects to the Destination Bucket

Use the aws s3 cp command to copy files from the source bucket to the destination bucket:

aws s3 cp s3://source-bucket-name s3://destination-bucket-name –recursive

This command recursively copies all objects from the source bucket to the destination bucket.

4. Verify the Transfer

To confirm that the files were successfully copied, list the objects in the destination bucket:

aws s3 ls s3://destination-bucket-name –recursive

If all files appear in the destination bucket, the transfer was successful.

5. Delete Objects from the Source Bucket (Optional)

After verifying the transfer, delete objects from the source bucket if needed:

aws s3 rm s3://source-bucket-name –recursive

This removes all objects from the source bucket, freeing up storage space.

Best Practices for S3 Data Transfers

  • Use S3 Transfer Acceleration – Enable transfer acceleration for faster object movement, especially for large datasets.
  • Enable Versioning – Maintain object versions to prevent accidental data loss.
  • Monitor Transfers – Use AWS CloudWatch for tracking S3 operations and performance.
  • Use AWS DataSync – For large-scale migrations, AWS DataSync offers an optimized transfer mechanism.

Conclusion

Transferring objects between S3 buckets using AWS CLI is an efficient and straightforward process. By following the outlined steps, users can successfully move, verify, and manage S3 objects while ensuring best practices for data security and performance.