Comment 10 for bug 1523779

here is my working config:
partitioning_commands:
  builtin: [curtin, block-meta, custom]
storage:
  config:
  - {id: sda, model: IPR-0 5EC29C00, name: sda, ptable: gpt, serial: IBM_IPR-0_5EC29C0000000080, type: disk, wipe: superblock}
  - {device: sda, grub_device: true, id: sda-part1, name: sda-part1, number: 1, flag: prep, offset: 4194304B, size: 8388608B, type: partition, wipe: zero}
  - {device: sda, id: sda-part2, name: sda-part2, number: 2, offset: 12582912B, size: 283778220032B, type: partition, uuid: 6193de67-6b76-4cb6-bf6d-25518842d54b, wipe: superblock}
  - devices: [sda-part2]
    id: vgroot
    name: vgroot
    type: lvm_volgroup
    uuid: 93d1991a-9631-4051-81dd-c60d3267f23b
  - {id: vgroot-lvroot, name: lvroot, size: 283774025728B, type: lvm_partition, volgroup: vgroot}
  - {fstype: ext4, id: vgroot-lvroot_format, label: root, type: format, uuid: efdcbb0b-b9ca-455f-8cf9-1dbfc820717a, volume: vgroot-lvroot}
  - {device: vgroot-lvroot_format, id: vgroot-lvroot_mount, path: /, type: mount}
  version: 1