My users are mostly road warriors who work on their Windows laptops. I would like to have a backup solution that would copy data to a corporate server over VPN. Could is absolutely out of question. It has to:
- support flaky connections and interrupted syncs gracefully
- user should be able to throttle transfer
- Ideally, it should support multiple backup partnerships - some directories get backed up to server A, and some to server B.
I don't really need any sync, just a way not to lose data. Something simple and robust is preferred to very complex and enterprisy - I can achieve versioning with server snapshots.
I don't mind paying as long as it isn't a lot (ZManda's $150/y per client is a lot)
I use Burp http://burp.grke.net for my backup needs, it meets your requirements and it is open source. I personally use it on CentOS and Windows 7 boxes with great success.
CrashPlan (peer-to-peer) may meet your needs.
It's not transparent but it may do.
I'm quite unsure how effective it would be in your situation but I've been playing around with Genie Timeline lately and have been able to use it over a VPN connection. It may be worth a look.