(Alternative product recommendation, please downvote/remove if you feel that isn't appropriate) For Unix/Linux backups, may I suggest Borg Backup? It encrypts and does dedupe astonishingly well. It also works over SSH incredibly fast, and restores are via a mounted FUSE filesystem so they're easy to pick and choose what you need. It prunes really well too, and is a single executable so it's easy to distribute via Ans…
Sadly, the only thing I've found so far that works at all at those scales is Bacula, and that is file-based -- i.e., if you have a gigabyte file that changes by one byte, it backs up the whole gigabyte again. Not ideal.