Backup a folder to a remote server

I've been thinking about getting an offsite backup for my photos for a while now. I've got a 2 disk RAID backup in the house, but I'd be devastated if my house caught fire/my kit got lost etc and I lost all of my digital photos right from when I studied it at 14, through to now when I teach photography.

So I've got a seedbox/cloud server anyway and I was thinking I could dedicate a folder on that and then use a piece of software to 'sync' or backup the folder to the server at scheduled times (the middle of the night). I can used ftp or ssh to do this, but I'd rather use ssh for security. Does anyone know of any applications that will be able to achieve this?