I have two windows servers one being at my house running windows server 2012 r2 setup with FTP, VPN and other services. The other being at a friend s home off site. He runs windows 10. On my server I have two 10 tb hard drives that sync. I threw a 10tb harddrive in his computer in hopes to have an off site backup location. The problem is I ve been trying to use Goodsync through ftp on his end but it never completes a transfer. what method is used professionally for offsite backup without paying a third party for storage such as dropbox.