Subject: No partition a in a cd disklabel
To: None <tech-kern@netbsd.org>
From: Richard Earnshaw <rearnsha@buzzard.freeserve.co.uk>
List: tech-kern
Date: 04/28/2004 20:11:58
I've just built a 2.0_BETA boot cdrom for my cats machine, and I was 
surprised to discover on booting it, that the default configuration can't 
install from the cdrom.

The problem seems to be that the manufactured disk label for the drive 
(I'm assuming they're manufactured for CDs, it certainly says that it's 
fictitious) only has a partition 'c' and no partition 'a'.  That means 
that the defaults in sysinst (/dev/cd0a) for the mount leads to the error 
"Device not configured" -- only you don't see that because sysinst hides 
it, you find that out only on deeper investigation.  Using cd0c works 
fine, so I don't think it's the drive at fault.

/sbin/disklabel /dev/rcd0c
disklabel: Can't read master boot record 0: Invalid argument
# /dev/rcd0c:
type: ATAPI
disk: mydisc
label: fictitious
flags: removable
bytes/sector: 2048
sectors/track: 100
tracks/cylinder: 1
sectors/cylinder: 100
cylinders: 655
total sectors: 65410
rpm: 300
interleave: 1
trackskew: 0
cylinderskew: 0
headswitch: 0           # microseconds
track-to-track seek: 0  # microseconds
drivedata: 0 

8 partitions:
#        size    offset     fstype [fsize bsize cpg/sgs]
 c:    261640         0    ISO9660       0             # (Cyl.      0 -   
2616+)
disklabel: boot block size 0
disklabel: super block size 0
disklabel: partition c: partition extends past end of unit


It's not just the INSTALL kernel that's faulty, normal kernels seem to be 
this way as well.

Has the disklabel code changed recently?  Or should I be filing yet 
another cats bug report.

R.