Rsync is used for all copying to backup media.

Backup to internal hard Disk

Mirror new files on SSD to HDD.

karl@erlangen:~> time rsync -av /home/Albums/ /home-HDD/backup/home/Albums/
sending incremental file list

sent 4,492,931 bytes  received 11,148 bytes  3,002,719.33 bytes/sec
total size is 185,751,103,178  speedup is 41,240.64

real    0m0,720s
user    0m0,359s
sys     0m0,360s
karl@erlangen:~> 

Backup to external hard Disk

External disks are used for syncing machines. Specify '--delete' to avoid transfer of stale files.

karl@erlangen:~> time rsync -nav --delete /home/Albums/Bilder/ /run/media/karl/WD25/backup/home/Albums/Bilder/
sending incremental file list

sent 1,448,755 bytes  received 4,831 bytes  2,907,172.00 bytes/sec
total size is 160,243,360,852  speedup is 110,240.03 (DRY RUN)

real    0m0,369s
user    0m0,138s
sys     0m0,233s
karl@erlangen:~>