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• What do you want to restore from your backup or archive? Specific files? All files as of a specific date? 
• How fast do you need it? I.e., what is your Recovery Time Objective (RTO)?
• What is your Recovery Point Objective (RPO)? I.e. how far out-of-date can objects be when restored?
  • E.g., A server RPO may be 24 hours, meaning that its OK to have restored files be as much as 24 hours old, but no older.
• Should different versions of backed-up/archive objects be kept? Or, do you always want the latest version?
• How often do you envision having to restore data?
  • Some service pricing is fairly expensive when you actually need to restore data, especially in short timeframes.
• What are the basic metrics of the data in scope for your use case?
  • Total cumulative size of target data?
  • Total number of target files/objects?
  • Total number of target files/objects < 128KB?
    • Some services handle smaller objects differently than larger objects
  • Estimated number of target files/objects deleted before 90 days
    • Some services require a minimum object lifetime and will charge you for storing the object for the entirety of that period, even if the object is deleted before reaching that age.

General Approaches

There are a lot of pathways to get on-premise files to S3 or other AWS services. Picking the right one will depend on your use case, budget, ability or desire to tinker and monitor costs, and palatability of deploying additional on-premises resources.

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• AWS Backup
• EBS Snapshots
• RDS Snapshots
• S3 Replication
• ... 

Resources

Internal

• SFTP and Cloud Object Store Clients - OS X and Windows
• S3 Sync Analysis – Analyzes S3 API-costs of various rclone settings

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