boot-requirements.md

Y2Storage::BootRequirementsChecker

needed partitions in an aarch64 system

• with a partitions-based proposal
  • if there are no EFI partitions
    • requires only a new /boot/efi partition
  • if there is already an EFI partition
    • and it is not a suitable EFI partition (not enough size, invalid filesystem)
      • requires only a new /boot/efi partition
    • and it is a suitable EFI partition (enough size, valid filesystem)
      • and it is on the boot disk
        • only requires to use the existing EFI partition
      • and it is not on the boot disk
        • requires only a new /boot/efi partition
• with a LVM-based proposal
  • if there are no EFI partitions
    • requires only a new /boot/efi partition
  • if there is already an EFI partition
    • and it is not a suitable EFI partition (not enough size, invalid filesystem)
      • requires only a new /boot/efi partition
    • and it is a suitable EFI partition (enough size, valid filesystem)
      • and it is on the boot disk
        • only requires to use the existing EFI partition
      • and it is not on the boot disk
        • requires only a new /boot/efi partition
• with an encrypted proposal
  • if there are no EFI partitions
    • requires only a new /boot/efi partition
  • if there is already an EFI partition
    • and it is not a suitable EFI partition (not enough size, invalid filesystem)
      • requires only a new /boot/efi partition
    • and it is a suitable EFI partition (enough size, valid filesystem)
      • and it is on the boot disk
        • only requires to use the existing EFI partition
      • and it is not on the boot disk
        • requires only a new /boot/efi partition
• with an AutoYaST profile that places '/' in a LUKS2 device
  • if there are no EFI partitions
    • requires new partitions for /boot/efi and for /boot (Grub2 auto-config cannot handle LUKS2)
  • if there is already a suitable EFI partition in the boot disk
    • requires to reuse EFI and create a /boot partition (Grub2 auto-config cannot handle LUKS2)

needed partitions in a PPC64 system

• in a non-PowerNV system (KVM/LPAR)
  • with a partitions-based proposal
    • if there are no suitable PReP partitions in the target disk
      • requires only a new PReP partition (to allocate Grub2)
      • does not require a separate /boot partition (Grub2 can handle this setup)
    • if there is already a suitable PReP partition in the disk
      • and it is on the boot disk
        • does not require any partition (PReP will be reused and Grub2 can handle this setup)
      • and it is not on the boot disk
        • requires only a new PReP partition (to allocate Grub2)
  • with a LVM-based proposal
    • if there are no suitable PReP partitions in the target disk
      • requires only a new PReP partition (to allocate Grub2)
      • does not require a separate /boot partition (Grub2 can handle this setup)
    • if there is already a suitable PReP partition in the disk
      • and it is on the boot disk
        • does not require any partition (PReP will be reused and Grub2 can handle this setup)
      • and it is not on the boot disk
        • requires only a new PReP partition (to allocate Grub2)
  • with an encrypted proposal
    • if there are no suitable PReP partitions in the target disk
      • requires only a new PReP partition (to allocate Grub2)
      • does not require a separate /boot partition (Grub2 can handle this setup)
    • if there is already a suitable PReP partition in the disk
      • and it is on the boot disk
        • does not require any partition (PReP will be reused and Grub2 can handle this setup)
      • and it is not on the boot disk
        • requires only a new PReP partition (to allocate Grub2)
  • with an AutoYaST profile that places '/' in a LUKS2 device
    • if there are no suitable PReP partitions in the target disk
      • requires a new PReP and a new /boot partition (Grub2 auto-config cannot handle LUKS2)
    • if there is already a suitable PReP partition in the disk
      • and it is on the boot disk
        • requires a separate /boot partition (Grub2 auto-config cannot handle LUKS2)
      • and it is not on the boot disk
        • requires a new PReP and a new /boot partition (Grub2 auto-config cannot handle LUKS2)
• in bare metal (PowerNV)
  • with a partitions-based proposal
    • does not require any booting partition (no Grub stage1, PPC firmware parses grub2.cfg)
  • with a LVM-based proposal
    • does not require a PReP partition (no Grub stage1, PPC firmware parses grub2.cfg)
    • requires only a /boot partition (for the PPC firmware to load the kernel)
  • with an encrypted proposal
    • does not require a PReP partition (no Grub stage1, PPC firmware parses grub2.cfg)
    • requires only a /boot partition (for the PPC firmware to load the kernel)
• when proposing a boot partition
  • requires /boot to be a non-encrypted ext4 partition in the booting disk
  • when aiming for the recommended size
    • requires /boot to be at least 200 MiB large
  • when aiming for the minimal size
    • requires /boot to be at least 100 MiB large
• when proposing a PReP partition
  • requires it to be on the boot disk
  • requires it to be a non-encrypted partition
  • requires it to be bootable (ms-dos partition table) for some firmwares to find it
  • requires it to be primary since some firmwares cannot find logical partitions
  • requires no particular position for it in the disk (since there is no evidence of such so far)
  • when aiming for the recommended size
    • requires it to be at least 4 MiB (Grub2 stages 1+2, needed Grub modules and extra space)
    • requires it to be at most 8 MiB (some firmwares will fail to load bigger ones)
  • when aiming for the minimal size
    • requires it to be at least 2 MiB (Grub2 stages 1+2 and needed Grub modules)
    • requires it to be at most 8 MiB (some firmwares will fail to load bigger ones)

needed partitions in a Raspberry Pi

• if the target boot disk initially contains a MBR partition table
  • and the first partition in the boot disk has id DOS32 and a FAT filesystem
    • and it contains an EFI directory
      • only requires to use the existing EFI partition (bootcode will be installed there)
    • and it contains a Raspberry Pi boot code but no EFI directory
      • and there is also a suitable standard EFI partition in the target disk
        • requires to mount at /boot/vc the firmware partition from the target disk
        • requires to use the existing EFI partition
      • and there is no suitable EFI partition in the target disk
        • requires to mount at /boot/vc the firmware partition from the target disk
        • requires a new /boot/efi partition
        • does not enforce the /boot/efi partition to be the first
        • requires the /boot/efi partition to have id ESP (according to the EFI standard)
    • and the first partition contains no boot code or EFI files
      • requires only a new /boot/efi partition
      • requires /boot/efi to be the first partition of the device
      • requires /boot/efi to be in a MBR partition table, bumping any existing table if needed
      • requires the /boot/efi partition to have id DOS32 (bootcode will be installed there)
    • and there are no partitions in the boot disk
      • requires only a new /boot/efi partition
      • requires /boot/efi to be the first partition of the device
      • requires /boot/efi to be in a MBR partition table, bumping any existing table if needed
      • requires the /boot/efi partition to have id DOS32 (bootcode will be installed there)
  • and the first partition in the boot disk is a standard EFI with id ESP
    • requires only a new /boot/efi partition
    • requires /boot/efi to be the first partition of the device
    • requires /boot/efi to be in a MBR partition table, bumping any existing table if needed
    • requires the /boot/efi partition to have id DOS32 (bootcode will be installed there)
• if the target boot disk initially contains a GPT partition table
  • even if the first partition has id DOS32 and a FAT filesystem with an EFI system
    • requires only a new /boot/efi partition
    • requires /boot/efi to be the first partition of the device
    • requires /boot/efi to be in a MBR partition table, bumping any existing table if needed
    • requires the /boot/efi partition to have id DOS32 (bootcode will be installed there)
  • if there are no partitions in the boot disk
    • requires only a new /boot/efi partition
    • requires /boot/efi to be the first partition of the device
    • requires /boot/efi to be in a MBR partition table, bumping any existing table if needed
    • requires the /boot/efi partition to have id DOS32 (bootcode will be installed there)
• if the target boot disk contains no partition table initially
  • requires only a new /boot/efi partition
  • requires /boot/efi to be the first partition of the device
  • requires /boot/efi to be in a MBR partition table, bumping any existing table if needed
  • requires the /boot/efi partition to have id DOS32 (bootcode will be installed there)
• when proposing a new EFI partition
  • requires /boot/efi to be on the boot disk
  • requires /boot/efi to be a non-encrypted vfat partition
  • requires /boot/efi to be close enough to the beginning of disk
  • when aiming for the recommended size
    • does not enforce FAT32 or 16 for /boot/efi (FAT size will be decided by mkfs.vfat)
    • requires /boot/efi to be exactly 128 MiB large
  • when aiming for the minimal size
    • does not enforce FAT32 or 16 for /boot/efi (FAT size will be decided by mkfs.vfat)
    • requires /boot/efi to be exactly 128 MiB large

needed partitions in a S/390 system

• trying to install in a FBA DASD disk
  • with a partitions-based proposal
    • not using Btrfs (i.e. /boot is within a XFS or ext2/3/4 partition)
      • does not require additional partitions (the firmware can find the kernel)
    • using Btrfs (i.e. /boot is not in XFS or ext2/3/4)
      • requires only a separate /boot/zipl partition (to allocate Grub2+kernel+initrd)
  • with a LVM-based proposal
    • requires only a /boot/zipl partition (to allocate Grub2+kernel+initrd)
  • with an encrypted proposal
    • requires only a /boot/zipl partition (to allocate Grub2+kernel+initrd)
  • with an AutoYaST profile that places '/' in a LUKS2 device
    • requires only a /boot/zipl partition (to allocate Grub2+kernel+initrd)
• trying to install in a zFCP disk (no DASD)
  • with a partitions-based proposal
    • not using Btrfs (i.e. /boot is within a XFS or ext2/3/4 partition)
      • does not require additional partitions (the firmware can find the kernel)
    • using Btrfs (i.e. /boot is not in XFS or ext2/3/4)
      • requires only a separate /boot/zipl partition (to allocate Grub2+kernel+initrd)
  • with a LVM-based proposal
    • requires only a /boot/zipl partition (to allocate Grub2+kernel+initrd)
  • with an encrypted proposal
    • requires only a /boot/zipl partition (to allocate Grub2+kernel+initrd)
  • with an AutoYaST profile that places '/' in a LUKS2 device
    • requires only a /boot/zipl partition (to allocate Grub2+kernel+initrd)
• trying to install in a (E)CKD DASD disk
  • if the disk is formatted as LDL
    • raises an error (no proposal possible in such disk) - FIXME: why?
  • if the disk is formatted as CDL
    • with a partitions-based proposal
      • not using Btrfs (i.e. /boot is within a XFS or ext2/3/4 partition)
        • does not require additional partitions (the firmware can find the kernel)
      • using Btrfs (i.e. /boot is not in XFS or ext2/3/4)
        • requires only a separate /boot/zipl partition (to allocate Grub2+kernel+initrd)
    • with a LVM-based proposal
      • requires only a /boot/zipl partition (to allocate Grub2+kernel+initrd)
    • with an encrypted proposal
      • requires only a /boot/zipl partition (to allocate Grub2+kernel+initrd)
    • with an AutoYaST profile that places '/' in a LUKS2 device
      • requires only a /boot/zipl partition (to allocate Grub2+kernel+initrd)
• when proposing a /boot/zipl partition
  • requires /boot/zipl to be on the boot disk
  • requires /boot/zipl to be a non-encrypted partition
  • requires /boot/zipl to be formatted as ext2
  • requires /boot/zipl to be at most 300 MiB (anything bigger would mean wasting space)
  • when aiming for the recommended size (first proposal attempt)
    • requires /boot/zipl to be at least 200 MiB (Grub2, one kernel+initrd and extra space)
  • when aiming for the minimal size
    • requires /boot/zipl to be at least 100 MiB (Grub2 and one kernel+initrd)

needed partitions in a x86 system

• using UEFI
  • with a partitions-based proposal
    • if there are no EFI partitions
      • requires only a new /boot/efi partition
    • if there is already an EFI partition
      • and it is not a suitable EFI partition (not enough size, invalid filesystem)
        • requires only a new /boot/efi partition
      • and it is a suitable EFI partition (enough size, valid filesystem)
        • and it is on the boot disk
          • only requires to use the existing EFI partition
        • and it is not on the boot disk
          • requires only a new /boot/efi partition
  • with a LVM-based proposal
    • if there are no EFI partitions
      • requires only a new /boot/efi partition
    • if there is already an EFI partition
      • and it is not a suitable EFI partition (not enough size, invalid filesystem)
        • requires only a new /boot/efi partition
      • and it is a suitable EFI partition (enough size, valid filesystem)
        • and it is on the boot disk
          • only requires to use the existing EFI partition
        • and it is not on the boot disk
          • requires only a new /boot/efi partition
  • with an encrypted proposal
    • if there are no EFI partitions
      • requires only a new /boot/efi partition
    • if there is already an EFI partition
      • and it is not a suitable EFI partition (not enough size, invalid filesystem)
        • requires only a new /boot/efi partition
      • and it is a suitable EFI partition (enough size, valid filesystem)
        • and it is on the boot disk
          • only requires to use the existing EFI partition
        • and it is not on the boot disk
          • requires only a new /boot/efi partition
  • with an AutoYaST profile that places '/' in a LUKS2 device
    • if there are no EFI partitions
      • requires new partitions for /boot/efi and for /boot (Grub2 auto-config cannot handle LUKS2)
    • if there is already a suitable EFI partition in the boot disk
      • requires to reuse EFI and create a /boot partition (Grub2 auto-config cannot handle LUKS2)
• not using UEFI (legacy PC)
  • with GPT partition table
    • in a partitions-based proposal
      • if there is no GRUB partition
        • requires a new GRUB partition
      • if there is already a GRUB partition
        • and it is on the boot disk
          • does not require any particular volume
        • and it is not on the boot disk
          • requires a new GRUB partition
    • in a LVM-based proposal
      • if there is no GRUB partition
        • requires a new GRUB partition
      • if there is already a GRUB partition
        • and it is on the boot disk
          • does not require any particular volume
        • and it is not on the boot disk
          • requires a new GRUB partition
    • in an encrypted proposal
      • if there is no GRUB partition
        • requires a new GRUB partition
      • if there is already a GRUB partition
        • and it is on the boot disk
          • does not require any particular volume
        • and it is not on the boot disk
          • requires a new GRUB partition
    • with an AutoYaST profile that places '/' in a LUKS2 device
      • if there is no GRUB partition
        • requires new GRUB and /boot partitions (Grub2 auto-config cannot handle LUKS2)
      • if there is already a GRUB partition
        • and it is on the boot disk
          • requires a new /boot partition (Grub2 auto-config cannot handle LUKS2)
        • and it is not on the boot disk
          • requires new GRUB and /boot partitions (Grub2 auto-config cannot handle LUKS2)
  • with a MS-DOS partition table
    • if the MBR gap is big enough to embed Grub
      • in a partitions-based proposal
        • does not require any particular volume
      • in a LVM-based proposal
        • does not require any particular volume
      • in an encrypted proposal
        • does not require any particular volume
      • with an AutoYaST profile that places '/' in a LUKS2 device
        • requires a new /boot partition (Grub2 auto-config cannot handle LUKS2)
    • with a MBR gap too small to accommodate Grub
      • in a partitions-based proposal
        • if the file-system selected for / can embed grub (ext2/3/4 or btrfs)
          • does not require any particular volume
        • if the file-system selected for / cannot embed grub (eg. XFS)
          • requires a new /boot partition to install Grub into it
      • in a LVM-based proposal
        • if the file-system selected for / can embed grub (ext2/3/4 or btrfs)
          • requires a new /boot partition to install Grub into it
        • if the file-system selected for / cannot embed grub (eg. XFS)
          • requires a new /boot partition to install Grub into it
      • in an encrypted proposal
        • if the file-system selected for / can embed grub (ext2/3/4 or btrfs)
          • requires a new /boot partition to install Grub into it
        • if the file-system selected for / cannot embed grub (eg. XFS)
          • requires a new /boot partition to install Grub into it
  • when proposing a boot partition
    • requires /boot to be a non-encrypted ext4 partition in the booting disk
    • when aiming for the recommended size
      • requires /boot to be at least 200 MiB large
    • when aiming for the minimal size
      • requires /boot to be at least 100 MiB large
  • when proposing a new GRUB partition
    • requires it to be on the boot disk
    • requires it to have the correct id
    • requires it to be a non-encrypted partition
    • when aiming for the recommended size
      • requires it to be at least 4 MiB (Grub2 stages 1+2, needed Grub modules and extra space)
      • requires it to be at most 8 MiB (anything bigger would mean wasting space)
    • when aiming for the minimal size
      • requires it to be at least 2 MiB (Grub2 stages 1+2 and needed Grub modules)
      • requires it to be at most 8 MiB (anything bigger would mean wasting space)
  • when proposing a new EFI partition
    • requires /boot/efi to be on the boot disk
    • requires /boot/efi to be a non-encrypted vfat partition
    • requires /boot/efi to be close enough to the beginning of disk
    • when aiming for the recommended size
      • requires /boot/efi to use FAT32
      • requires it to be at least 256 MiB (min size for FAT32 in drives with 4-KiB-per-sector)
      • requires it to be at most 512 MiB (enough space for several operating systems)
    • when aiming for the minimal size
      • does not enforce FAT32 or 16 for /boot/efi (FAT size will be decided by mkfs.vfat)
      • requires it to be at least 128 MiB (MS Windows requires 100 MiB for itself)
      • requires it to be at most 512 MiB (enough space for several operating systems)