start   size  index  contents
      0      1         PMBR
      1      1         Pri GPT header
      2     32         Pri GPT table
     34   1024      1  GPT part - EFI System
   1058   9150      2  GPT part - NetBSD FFSv1/FFSv2
  10208     32         Sec GPT table
  10240      1         Sec GPT header