Tarsnap costs 2-3x more than Amazon S3, and S3 is already several times more expensive than it should be. What is the advantage of Tarsnap over S3 and one of its many clients?
Tarsnap also does encryption and compression. Now you might be able to implement something like that better then cperciva, but I know I sure as hell am not capable of implementing any system as secure as reliable as him. Does this knowledge cost money? Yes. Is it worth it? Well, that depends on you.
As does CrashPlan, and deduplication too, and it's cheaper than S3. It also runs on Solaris, Windows, etc., using file system monitoring to pick up changes.
Is that offer still available? I was under the impression that any new subscribers had to pay a monthly fee and it had been that way for a year or more.
Efficient secure Snapshotted backups. It says so in the 'Design' section. (maybe that ought to be on the front page as well)
http://www.tarsnap.com/design.html
One point which rarely gets mentioned is that to use S3 you need to have the access codes on the server. So theoretically a malicious individual could break into your server and delete all your files on that box and then wipe all the files on S3.
Tarsnap enables you to separate out the ability to write/read/delete. So a compromised box could at worst be used to inflate your tarsnap bill but not to wipe out all your backups.
S3/AWS multi-factor authentication, in combination with bucket versioning, ensures that if you can keep a redundant offsite record of your key and version information, you can always retrieve your data. An attacker requires your key fob to permanently delete an item. Of course, you'll need to physically secure your key fob.
It has been a while since I looked at S3 and didn't spot multi-factor authentication at the time. At only $13for the fob it seems like an interesting alternative.
