Host Primary Disk, is telling the system what DEVICE to look at. Device labels in linux are /dev/sd[a-z] or what not. Partions are what usually labeled as /dev/sda1 /dev/sda2 etc… So in the most literal of senses, You’re telling the system to look at DEVICE called: /dev/sda1, The FOG System is going to try looking for a partition on /dev/sda1 as /dev/sda11