Use the Backup Function:
"Local backup"
This function allows backing up shares on logical volumes of the Open-e NAS
server. Before starting a local backup procedure, you must choose the "source lv",
snapshot, destination and share source. Choosing the "incremental backup" will copy files that have been changed since the last backup or will make a new backup.
Shares included in the right window (see the image below), are automatically
backed up by clicking the "apply" button.

Additionally in the NAS-XSR you have additional synchronization, which can also synchronize between two shares on the same system.