I’m duplicating my server hardware and moving the second set off site. I want to keep the data live since the whole system will be load balanced with my on site system. I’ve contemplated tools like syncthing to make a 1 to 1 copy of the data to NAS B but i know there has to be a better way. What have you used successfully?
Better options have already been mentioned. With that said another option might be torrenting.
You would need to create a new torrent whenever new files are added or edited. Not very practical for continuous use.