Based on other similar threads in this forum, the problem is that it's looking for the CDROM but it's not there. One possible fix is to put the CDROM in. Another, apparently, is to copy the CDROM files to /dev/cdrom/ (or something like that). Another, is to use the "poor man's install" (which essentially emulates the CDROM from a hard drive file).

In any case, the client is going to be running whatever's on the CDROM image, not the hard drive install files.

I'm working on my own diskless network boot solution, using clusterKnoppix. I'm still not clear on a lot of details, but I think my best solution will involve customizing/remastering with "poor man's install" to get what I want rather than using a traditional hard drive install.