Rsync is a network protocol used to synchronize directories and data. It provides block level file replication and is suitable for data backup environments where file and directory data changes frequently.
To use Rsync to back up local ASUSTOR NAS data to another ASUSTOR NAS, you’ll need to go to Remote Sync inside Backup and Restore to create a new backup task.
When starting a new backup task, select ‘Your NAS - > Another ASUSTOR NAS’, enter the IP address of the target ASUSTOR NAS, select 1-to-1 folder backup.
1-1 backups ensure that source folders and folder structure will be identical on the destination.
Learn more here: https://www.asustor.com/online/College_topic?topic=259