for host in /sys/class/scsi_host/*; do echo "- - -" | sudo tee $host/scan; ls /dev/sd* ; done
Source:
https://unix.stackexchange.com/questions/404405/how-to-detect-new-hard-disk-attached-without-rebooting/500280#500280?s=a878dbdf0ffd4699bcb88957b7c1c087