dracut-initqueue[197]: Warning: Could not boot, ... /dev/root does not exist

[John Reiser]

> I am booting from a DVD via a usb device.  The computer only has a cd drive and the Live-Desktop image is > 700 MB so I have to use a DVD to boot the Desktop DVD.

One of my boxes has CD only, and USB1.1 only.  I plug in an external DVD
with USB2.0 interface into a PCMCIA (cardbus) card which has USB2.0 ports.
With the full DVD in the external drive, then I boot netinst.iso from
internal CD, changing the kernel parameter to

   root=cd:LABEL=the_actual_label

where any <Space> characters in the DVD label should be entered as "\\x20"
using two backslashes (one for the bootstrap program, one to pass along.)
In case of total disaster:

   root=/dev/sr1    # or whatever the actual DVD device is;
                    # look when some existing linux is running.

The most important part is, what is the actual label?
In the dracut emergency shell:

   cd /dev/disk/by-label
   echo *

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