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Five tips for optimizing your cloud backups

I'd add that the smartest tools will be able to perform block-level change hashes; rather than re-transfer an entire file.

Another thing to look for is to ensure that the backup mechanism can support delete restore. What I mean by that is if file A is deleted from source, the cloud backup solution doesn't correspondingly remove it from the cloud repository. There are cloud backup tools that work that way.

The above 5 points could be lifesavers when you truly have more data or have truly insufficient bandwidth speeds.

However, do note that even if you have the sufficient bandwidth, your cloud backup solution might not use it efficiently. This is because some products enforce artificial speed limits once you cross some usage threshold and some products simply are not efficient enough.

We have just announced Zmanda Cloud Backup 4 which features configurable multithreading to speed up the data transfer speeds to cloud. And of course, it offers options to store data on-premise, enforce bandwidth throttling, perform incremental/differential backups, etc. so that you can also make use of the 5 ideas suggested in this blog post. You can read up more here: http://www.zmanda.com/blogs/?p=435

b4real makes a good point too - "delete restore" support is important and surprisingly many cloud backup solutions simply delete files from the cloud once they get deleted from the user computers.