Bootloader problems

[Dave Huang <khym%azeotrope.org@localhost>]

I recently got a shiny new computer and want to install NetBSD on
it... however, I'm having some problems getting it to boot from the
hard drive (it boots from the install CD fine).

It's got an SSD, a large hard drive, and 4 smaller drives in a RAID
(onboard Intel RAID).

The SSD has a GPT with 3 partitions: FAT EFI System Partition, some MS
Reserved partition, and an NTFS partition. Windows 7 is installed on
the drive.

The large HD has a MBR, and has two partitions: one NTFS and one
NetBSD. The NetBSD partition is marked as active in the MBR.

The RAID is GPT and has a MS Reserved partition and a NTFS data
partition.

I use the BIOS boot selector (or I guess it's the UEFI boot selector?
The firmware boot selector, in any case) to boot the drive with the
NetBSD partition, and I get the NetBSD boot prompt:

NetBSD/x86 ffsv2 Primary Bootstrap


>> NetBSD/x86 BIOS Boot, Revision 5.9 (from NetBSD 6.0_BETA2)
>> Memory: 583/523264 k
Press return to boot now, any other key for boot menu
booting hd0a:netbsd - starting in 0 seconds.
open netbsd:  Input/output error
boot: hd0a:netbsd:  Input/output error
booting hd0a:netbsd.gz
open netbsd.gz:  Input/output error
boot: hd0a:netbsd.gz: Input/output error
[ I press a key to get a prompt ]
> dev
disk hd0 size 1863 GB
disk hd1 size 111 GB
  hd1a(unknown) hd1b(unknown) hd1c(unknown)
disk hd2 size 894 GB
  hd2a(unknown) hd2b(unknown)
disk fd0
  fd0a
disk fd1
  fd1a
default hd0a

hd0 is the drive with the NetBSD partition, but the bootloader doesn't
seem to see any of them? It does see the GPT partitions on the other
drives though (hd1 is the SSD, hd2 is the RAID).

fdisk shows:
Disk: /dev/rwd1d
NetBSD disklabel disk geometry:
cylinders: 3876021, heads: 16, sectors/track: 63 (1008 sectors/cylinder)
total sectors: 3907029168

BIOS disk geometry:
cylinders: 1023, heads: 255, sectors/track: 63 (16065 sectors/cylinder)
total sectors: 3907029168

Partitions aligned to 2048 sector boundaries, offset 63

Partition table:
0: NTFS, OS/2 HPFS, QNX2 or Advanced UNIX (sysid 7)
    start 206848, size 3824902144 (1867628 MB, Cyls 12/223/20-238102/5/47)
1: NetBSD (sysid 169)
    start 3825108992, size 81920176 (40000 MB, Cyls 238102/5/48-243201/80/63), 
Active
2: <UNUSED>
3: <UNUSED>
First active partition: 1
Drive serial number: 2051726421 (0x7a4adc55)

disklabel shows:
# /dev/rwd1d:
type: unknown
disk: WDC
label: 
flags:
bytes/sector: 512
sectors/track: 63
tracks/cylinder: 16
sectors/cylinder: 1008
cylinders: 3876021
total sectors: 3907029168
rpm: 3600
interleave: 1
trackskew: 0
cylinderskew: 0
headswitch: 0   # microseconds
track-to-track seek: 0  # microseconds
drivedata: 0 

16 partitions:
#        size    offset     fstype [fsize bsize cpg/sgs]
 a:  80870832 3825108992     4.2BSD   2048 16384     0  # (Cyl. 3794750*- 
3874979*)
 b:   1049344 3905979824       swap                     # (Cyl. 3874979*- 
3876020)
 c:  81920176 3825108992     unused      0     0        # (Cyl. 3794750*- 
3876020)
 d: 3907029168         0     unused      0     0        # (Cyl.      0 - 
3876020)

So, why does the bootloader see the GPT partitions and not the MBR? Do
all drives in the system have to use one partitioning scheme or the
other?

Also, I can supply a dmesg if it'll help.
-- 
Name: Dave Huang         |  Mammal, mammal / their names are called /
INet: khym%azeotrope.org@localhost |  they raise a paw / the bat, the cat /
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