So everyone backs their stuff up to the cloud. But I want to back up my stuff from the cloud.
For a planned SaaS service, users are saving files containing their intellectual property and we're saving them in S3. I'm not entirely comfortable with the only copy of a file they are entrusting to me being at a third party. So I'd like to do a good encrypted, deduping, etc. backup from S3 to my on premise (or even from AWS straight to Iron Mountain or something). Anyone have an idea for this (besides "write scripts," yes, I could do that, but I'm happier to use software somewhat meant for the purpose).
The thing that seems to disqualify most normal backup software is that it would need to consume Amazon S3 as a source (not a destination - I know a lot of stuff does it as the destination). I'd want it to encrypt the files and then put them somewhere and ideally not transfer files that haven't changed. I'm actually not all that picky about other details. It can be Linux or Windows based, I can run it on an instance in the cloud or on a server on my premises, it can use whatever transit protocol.
I imagine if there's a good production-ready "mount s3 as a drive" option, then really many backup programs could be brought to bear including "ssh+rsync". I see a couple of these but they all look sketchy.
Is anyone doing this or know how it might be most easily accomplished? Open source is good but I'm also willing to toss some money at it if it gets me nice features.