Genera 8.1 CD-ROM Problem

[morse@zephyr.rap.ucar.EDU (Corinne Morse)]

I am attempting to do an initial CD-ROM installation of Genera 8.1 on our
XL400.  After installing the CD-ROM hardware (a Sun CD-ROM drive), I
reset the XL400 and followed the instructions to load the FEP kernal from the 
XL bootstrap tape.  The SCSI ID of the CD-ROM drive was 4.  After powering up
the CD-ROM drive and inserting the CD-ROM, I did a disk restore:

FEP: Disk Restore 0 "chaos|3033" :source CART11: :format no :create paging
files no :standalone site no :query no

And then got the message:

[1991-09024 18:52;48 (GMT):: Restoring disk unit 0 from CART11:...
Superseding condition=>disk unit 0 at SCSI ID 4, status: 2, sense:5, 
additional-sense:32, sector NIL, reason: NIL
[Error: Error while opening CART11: UMAKE-INSTANCE on: closed NIL
<<Error printing #<DTP-ARRAY 37000555040>>> with REFERENCE-COUNT = NIL]

I tried this with the CD-ROM drive SCSI ID=6 also (CART13:) with the 
identical result. 

Has anyone else had a similar problem (and/or a solution)?  

Elsewhere Symbolics claims to have qualified only the Apple CD-ROM drive.
Is it likely that my Sun CD-ROM drive is the problem and that I should go
to plan B of using the CD-ROM on the Sun and reading over the network?

Thanks in advance,

Cory Morse  morse@zephyr.rap.ucar.edu   morse@ncar.ucar.edu