I have a number of bootable USB sticks, all 32 bit. These work fine on all my boxes, and work quite well with the one box that will actually _boot_ USB3. I would like to do a 64 bit variant of this and just tweaked an existing system to fit onto a 16 G USB stick. This starts off booting and then times out because it can't find the root device. Delving around in the minimalist emergency environment shows that the USB device is indeed not present - blkid shows all the other devices. The normal boot uses UUID identifiers and non-EFI. The kernel in the initramfs has all the USB drivers builtin. Btw - is there an easy way to unpick initramfs - I found I needed to lop off the uncompressed leading cpio to get at the gzipped cpio filesystem that followed? Any suggestions? Please.