|With seriously low power consumption and no noise, you can put one of these almost anywhere. The unmodified device is reviewed here. Click 'read more...' below for the mod article.|
After the Debian installer completes we need to boot from the selected root partition on the USB hard drive.
Unfortunately it isn't possibly to directly boot of an USB mass storage device as the detection and partition scan happens after the kernel tries to mount the rootfs.
Luckily there is a kernel cmdline option called 'rootdelay' which forces the kernel to wait the requested number of seconds before mounting the rootfs. Using rootdelay=10 seems to do it for me, but you might need to increase it for slow disks.