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Backup/recovery is a good use case for cloud storage. The two important attributes for a reliable backup solution are:

• Backup files should be off-site.
• Backup should be as close to real time as possible.

Traditionally, folks would backup data on tapes and transport them periodically to a safe storage location. While this is a good solution for backing up huge data, it is cumbersome due to the logistics involved during backup, as well as storage.

In the case of cloud storage, data is offsite and can be backed up on any schedule. Backup and restore is simple. The main drawback is the bandwidth required for very large data sets.

Usually for extremely large data backup, companies ship the data on disks and the cloud storage provider transfers the data to the cloud storage. As Werner Vogels, CTO of Amazon Cloud services observes, "Never underestimate the bandwidth of a FedEx box". Once this initial process is complete, ongoing backup is more efficient because only the changes to the dataset are backup up using the Internet.

First of all, the cloud storage should have a superset of all your data, organized in any reasonable fashion that makes sense to you.

• You may have separate folders for each office; the folders may be organized by function (marketing, sales, engineering, etc.).
• Home storage can be organized by computer (Dad, Mom, living room), or by function (music, letters, taxes, work).

Second, setup regular synchronization between the computers, at a minimum once every 12 hours, maybe more frequently. This ensures the worst case is you will lose 12 hours of data.

Third, you have to think about snapshots and revisions. This is to guard against data corruption by a program or human error. While frequent sync will guard against hardware problems, like a disk crash, it will not guard against other errors where wrong data can overwrite the correct data. A snapshot backup separate from the regular backup is essential. Another alternative is to keep three or four revisions of the files all the time.

Now that you have regular backups, recovery is easier. If a hard disk fails, replace the disk, install the operating system, install the local cloud software from the hybrid cloud provider, and sync! After these steps all of the files are back onto your disk.

Naturally the above is a general overview. You need to understand and work through the software and commands for the OS and hardware that is specific to your machine.