As you know is not possible to perform a rsync with a ftp site. Here you can find a simple workaround to perform a remote backup.

First install rsync and curlftpfs…

sudo apt-get install rsync curlftpfs

…then create the mountpoint and allow access to your user…

sudo mkdir /mnt/yourftp

sudo chown youruser /mnt/yourftp

…enable the fuse mount for non-root users…

sudo vi /etc/fuse.conf

uncomment the parameter user_allow_other on the last line

…and then mount your ftp site

curlftpfs -o user=username:password,allow_other ftp.yoursite.com /mnt/yourftp

Now you can navigate your ftp like a classic filesystem folder!

Finally enjoy your rsync (example):

rsync -r -t -v –progress –delete /home/folder_to_backup/ /mnt/yourftp

Remember that if you need to sync folders with different name you have to add the last slash on the source dir!

P.S. Don’t forget to unmount your ftp site after the rsync:

sudo umount /mnt/yourftp