This is for i386.  The dmsg output for this 2nd HD is:

wd1 at pciide0 channel 1 drive 0: <WDC WD450AA-00BAA0>
wd1: drive supports 16-sector PIO transfers, LBA addressing
wd1: 42934 MB, 16383 cyl, 16 head, 63 sec, 512 bytes/sect x 87930864 sectors
wd1: 32-bit data port
wd1: drive supports PIO mode 4, DMA mode 2, Ultra-DMA mode 4 (Ultra/66)
wd1(pciide0:1:0): using PIO mode 4, Ultra-DMA mode 4 (Ultra/66) (using DMA data
 transfers)

Unfortunately, a previous (erroneous) disklabel got written to this disk, which
produced (via "disklabel wd1 > foo")

# /dev/rwd1d:
type: unknown
disk: mydisk
label: 
flags:
bytes/sector: 512
sectors/track: 63
tracks/cylinder: 16
sectors/cylinder: 1008
cylinders: 16383
total sectors: 66055248
rpm: 3600
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]
  a:   567441       63     4.2BSD     1024  8192    16   # (Cyl.    0*- 562)
  b:  1051344   567504       swap                        # (Cyl.  563 - 1605)
  c: 66055185       63     unused        0     0         # (Cyl.    0*- 65530)
  d: 66055248        0     unused        0     0         # (Cyl.    0 - 65530)
  e: 64436400  1618848     4.2BSD     1024  8192     0   # (Cyl. 1606 - 65530)

Notice that the size is wrong.  So edited this to be:

# /dev/rwd1d:
#wd1: 42934 MB, 16383 cyl, 16 head, 63 sec, 512 bytes/sect x 87930864 sectors
type: unknown
disk: my2disk
label: 
flags:
bytes/sector: 512
sectors/track: 63
tracks/cylinder: 16
sectors/cylinder: 1008
cylinders: 16383
total sectors: 87930864
rpm: 3600
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]
  a:   567441       63     4.2BSD     1024  8192    16   # (Cyl.    0*- 562)
  b:  1051344   567504       swap                        # (Cyl.  563 - 1605)
  c: 87930801       63     unused        0     0         # (Cyl.    0*- 65530)
  d: 87930864        0     unused        0     0         # (Cyl.    0 - 65530)
  e: 86312016  1618848     4.2BSD     1024  8192     0   # (Cyl. 1606 - 65530)


In an attempt to use up all the space, but "disklabel -R -r wd1 foo" yields:

ioctl DIOCWLABEL: Inappropriate ioctl for device
ioctl DIOCWLABEL: Inappropriate ioctl for device

------------

What I'd really like to do is blow away this disklabel and keep only a duplicate
root partition (in case the one on wd0 gets hosed) and then then use the rest of
the disk to store data (no swap).

FWIW, the wd0 disk is:

d0 at pciide0 channel 0 drive 0: <IBM-DTLA-307030>
wd0: drive supports 16-sector PIO transfers, LBA addressing
wd0: 29314 MB, 16383 cyl, 16 head, 63 sec, 512 bytes/sect x 60036480 sectors
wd0: 32-bit data port
wd0: drive supports PIO mode 4, DMA mode 2, Ultra-DMA mode 5 (Ultra/100)
wd0(pciide0:0:0): using PIO mode 4, Ultra-DMA mode 5 (Ultra/100) (using DMA data transfers)

wd0 is connected to the first channel on a Promise PCI card, and the wd1 is
connected to the second channel on the Promise card; each is a master.

Incidentally, wd0 is 7200 RPM and wd1 is 5400 RPM, but disklabel in both cases
says "rpm: 3600"

Thanks for any help!

-Mike