Which solution meets these requirements MOST cost-effectively?
Configure Amazon Data Lifecycle Manager (Amazon DLM) to archive a copy of the data to an Amazon S3 Glacier vault. Use S3 Glacier retrieval requests to retrieve individual files.
Create a second EFS file system in another AWS Region. Configure AWS DataSync to copy the data to the backup file system. Recover files by copying them from the backup EFS file system.
Enable AWS Backup in Amazon EFS to back up the file system to an Amazon S3 Glacier vault. Use S3 Glacier retrieval requests to retrieve individual files.
Enable AWS Backup in Amazon EFS to back up the file system to a backup vault. Use a partial restore job to retrieve individual files.
Explanations:
Amazon Data Lifecycle Manager (DLM) is not used for Amazon EFS and does not provide direct support for EFS backups. This option is unsuitable for EFS and would not meet the recovery requirements.
Using DataSync to copy data to a second EFS file system in another region is costly and complex. It also does not provide rapid or easy access to individual file recovery.
While AWS Backup can archive to Amazon S3 Glacier, retrieving individual files from Glacier is slow and not cost-effective, especially for rapid individual file recovery.
AWS Backup for EFS supports backup to a backup vault with quick recovery options, including partial restore jobs, which enables rapid and cost-effective individual file recovery.
I conclude that the answer is:
Enable AWS Backup in Amazon EFS to back up the file system to a backup vault. Use a partial restore job to retrieve individual files.