Amazon S3 offers several mechanisms to prevent accidental or malicious deletion of your objects and buckets. These features are critical for ensuring data durability and protection against accidental loss.
S3 Versioning
What it Does:
Enables multiple versions of an object to be stored in a bucket.
When versioning is enabled, deleting an object does not remove it but instead creates a “delete marker,” preserving older versions.
S3 Object Lock
What it Does:
Prevents objects from being deleted or modified for a fixed retention period or indefinitely.
Enforces Write Once, Read Many (WORM) storage for regulatory compliance.
Object Lock Modes:
Governance Mode: Allows only authorized users to delete objects.
Compliance Mode: Prevents even root users from deleting objects during the retention period.
MFA Delete (Multi-Factor Authentication Delete)
What it Does:
Requires MFA (multi-factor authentication) to delete versioned objects or suspend bucket versioning.
Adds an additional layer of security by ensuring that only authorized users with physical access to the MFA device can delete objects.
Bucket Policies and IAM Permissions
What it Does:
Controls who can delete objects using fine-grained access policies.
Example: Restrict delete permissions for all users except specific roles or prevent deletion altogether.
AWS Backup for S3
What it Does:
Allows automated backups of S3 data with lifecycle policies and recovery options.
Ensures recoverability in case of accidental deletions or overwrites.
Lifecycle Policies for Deletion Control
What it Does:
Manages object lifecycles by automating actions such as transitioning to cheaper storage or expiring old versions.
Retains specific versions for a defined period before deletion.
CloudTrail for Monitoring Deletions
What it Does:
Monitors and logs all delete operations on your S3 bucket.
Helps identify who initiated deletions, what objects were deleted, and when.
Best Practices
Enable Versioning: To recover accidentally deleted objects.
Use Object Lock: For regulatory compliance or high-assurance WORM storage.
Apply MFA Delete: For sensitive or critical data requiring strong authentication.
Restrict Delete Permissions: Use IAM roles, bucket policies, or ACLs to prevent unauthorized deletions.
Enable CloudTrail: For auditing and monitoring delete activities.
Use Backups: Regularly back up your data using AWS Backup for additional recoverability.