overlay-beaglebone/scripts/disk_layout.json

{
  "hybrid_mbr": true,
  "metadata":{
    "block_size": 512,
    "fs_block_size": 4096
  },
  "parent": "legacy_disk_layout.json",
  "layouts":{
    "base":[
      {
        "num": 5,
        "blocks":"819200",
        "fs_blocks":"89600"
      },
      {
        "num": 3,
        "blocks":"819200",
        "fs_blocks":"89600"
      }
    ],
    "usb":[
      {
        "num": 5,
        "blocks":"819200",
        "fs_blocks":"89600"
      },
      {
        "num": 3,
        "blocks":"819200",
        "fs_blocks":"89600"
      }
    ]
  }
}