# disklabel wd1                                                                                                                     

Output:
# Inside MBR partition 3: type A6 start 100 size 4294967196
# /dev/rwd1c:
type: ESDI
disk: ESDI/IDE disk
label: Maxtor 98196H8  
flags:
bytes/sector: 512
sectors/track: 63
tracks/cylinder: 16
sectors/cylinder: 1008
cylinders: 16383
total sectors: 160086528
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]
  a:     160086465            63  4.2BSD   2048 16384   16 # Cyl     0*-158815 
  c:     160086528             0  unused      0     0      # Cyl     0 -158815 

fine.

# vnconfig -kc svnd0 /dev/wd1a 
# disklabel svnd0 

Output:
# /dev/rsvnd0c:
type: SCSI
disk: vnd device
label: fictitious
flags:
bytes/sector: 512
sectors/track: 100
tracks/cylinder: 1
sectors/cylinder: 100
cylinders: 0
total sectors: 536870911
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]
  c:     536870911             0  unused      0     0      # Cyl     0 -5368709*
disklabel: cylinders/unit 0

????