start     size  index  contents
      0        1         PMBR
      1        1         Pri GPT header
      2       32         Pri GPT table
     34       29         Unused
     63      500      1  GPT part - NetBSD FFSv1/FFSv2
    563     1000      2  GPT part - NetBSD swap
   1563     1000      3  GPT part - NetBSD FFSv1/FFSv2
   2563      400      4  GPT part - Windows basic data
   2963     7245         Unused
  10208       32         Sec GPT table
  10240        1         Sec GPT header