booting foreman-discovery-iso from hard disk

My team utilizes a vmware template that holds an iso copied to the /dev/sda disk with dd. Currently we use ipxe but we are switching to foreman. When I boot from the foreman iso I don't have any issues, but when I try dd if=foreman.iso of=/dev/sda, I see dracut timeout messages on reboot and a dracut shell. Has anyone else tried this or experienced this issue?