I only have a SFTP access on my NAS, on Lacie OS 3.X, (so exit rsync) and i want to backup it from a remote debian server.
The problem is that the NAS is 4TB and it can take a lot of time if i transfert all files everytimes.
Is there a simple way to do that, based on modification time and or file size in a small script or a command line ?
It seems that your NAS can be configured to perform remote backups (which appears to be what you want). This line is of interest
... It can also be a third-party NAS compatible with rsync.
In your case, the remote debian server should be considered a NAS. I expect you can configure rsyncd on it and then configure the NAS to use it as a target.
