i run a mixed windows and linux network with different desktops, notebooks and raspberry pis. i am trying to establish an off-site backup between a local raspberry pi and an remote raspberry pi. both run on dietpi/raspbian and have an external hdd with ntfs to store the backup data. as the data to be backuped is around 800GB i already initially mirrored the data on the external hdd, so that only the new files have to be sent to the remote drive via rsync.
i now tried various combinations of options including --ignore-existing --size-only -u -c und of course combinations of other options like -avz etc.
the problem is: nothing of the above really changes anything, the system tries to upload all the files (although they are remotely existing) or at least a good number of them.
could you give me hint how to solve this?