[CentOS] Booting from an external USB drive?

[James Pearson]

Bart Schaefer wrote:
> Is it possible?
> 
> Booting the installer from the CD works, finds the USB drive, and
> allows me to put the root filesystem on it.  I put the /boot partition
> on the internal hard drive and installed GRUB in the boot record of
> that partition.
> 
> GRUB shows the menu and begins booting, but eventually fails with the
> error that /dev/sda5 (the external partition) does not exist.
> 
> I was hoping (perhaps in vain) that initrd would provide the necessary
> modules/hooks to mount the USB device.  Is there some step of the
> installation that I'm missing, or something extra that I need to do by
> hand, like in the old days when LILO had to be explicitly told about
> SCSI cards?

My guess is that you will need to manually add the various usb and scsi 
drivers to the initrd image. You might even have to mount /proc/bus/usb 
at the initrd stage. Also check the initrd creates the necessary device 
files for your drive

James Pearson