Provided by: fdisk_2.38-4ubuntu1_amd64 bug


       sfdisk - display or manipulate a disk partition table


       sfdisk [options] device [-N partition-number]

       sfdisk [options] command


       sfdisk is a script-oriented tool for partitioning any block device. It runs in interactive
       mode if executed on a terminal (stdin refers to a terminal).

       Since version 2.26 sfdisk supports MBR (DOS), GPT, SUN and SGI disk labels, but no longer
       provides any functionality for CHS (Cylinder-Head-Sector) addressing. CHS has never been
       important for Linux, and this addressing concept does not make any sense for new devices.

       sfdisk protects the first disk sector when create a new disk label. The option --wipe
       always disables this protection. Note that fdisk(8) and cfdisk(8) completely erase this
       area by default.

       sfdisk (since version 2.26) aligns the start and end of partitions to block-device I/O
       limits when relative sizes are specified, when the default values are used or when
       multiplicative suffixes (e.g., MiB) are used for sizes. It is possible that partition size
       will be optimized (reduced or enlarged) due to alignment if the start offset is specified
       exactly in sectors and partition size relative or by multiplicative suffixes.

       The recommended way is not to specify start offsets at all and specify partition size in
       MiB, GiB (or so). In this case sfdisk aligns all partitions to block-device I/O limits (or
       when I/O limits are too small then to megabyte boundary to keep disk layout portable). If
       this default behaviour is unwanted (usually for very small partitions) then specify
       offsets and sizes in sectors. In this case sfdisk entirely follows specified numbers
       without any optimization.

       sfdisk does not create the standard system partitions for SGI and SUN disk labels like
       fdisk(8) does. It is necessary to explicitly create all partitions including whole-disk
       system partitions.

       sfdisk uses BLKRRPART (reread partition table) ioctl to make sure that the device is not
       used by system or other tools (see also --no-reread). It’s possible that this feature or
       another sfdisk activity races with systemd-udevd(8). The recommended way how to avoid
       possible collisions is to use --lock option. The exclusive lock will cause systemd-udevd
       to skip the event handling on the device.

       The sfdisk prompt is only a hint for users and a displayed partition number does not mean
       that the same partition table entry will be created (if -N not specified), especially for
       tables with gaps.


       The commands are mutually exclusive.

       [-N partition-number] device
           The default sfdisk command is to read the specification for the desired partitioning
           of device from standard input, and then create a partition table according to the
           specification. See below for the description of the input format. If standard input is
           a terminal, then sfdisk starts an interactive session.

           If the option -N is specified, then the changes are applied to the partition addressed
           by partition-number. The unspecified fields of the partition are not modified.

           Note that it’s possible to address an unused partition with -N. For example, an MBR
           always contains 4 partitions, but the number of used partitions may be smaller. In
           this case sfdisk follows the default values from the partition table and does not use
           built-in defaults for the unused partition given with -N. See also --append.

       -A, --activate device [partition-number...]
           Switch on the bootable flag for the specified partitions and switch off the bootable
           flag on all unspecified partitions. The special placeholder '-' may be used instead of
           the partition numbers to switch off the bootable flag on all partitions.

           The activation command is supported for MBR and PMBR only. If a GPT label is detected,
           then sfdisk prints warning and automatically enters PMBR.

           If no partition-number is specified, then list the partitions with an enabled flag.

       --backup-pt-sectors device
           Back up the current partition table sectors in binary format and exit. See the BACKING
           UP THE PARTITION TABLE section.

       --delete device [partition-number...]
           Delete all or the specified partitions.

       -d, --dump device
           Dump the partitions of a device in a format that is usable as input to sfdisk. See the

       -g, --show-geometry [device...]
           List the geometry of all or the specified devices. For backward compatibility the
           deprecated option --show-pt-geometry have the same meaning as this one.

       -J, --json device
           Dump the partitions of a device in JSON format. Note that sfdisk is not able to use
           JSON as input format.

       -l, --list [device...]
           List the partitions of all or the specified devices. This command can be used together
           with --verify.

       -F, --list-free [device...]
           List the free unpartitioned areas on all or the specified devices.

       --part-attrs device partition-number [attributes]
           Change the GPT partition attribute bits. If attributes is not specified, then print
           the current partition settings. The attributes argument is a comma- or space-delimited
           list of bits numbers or bit names. For example, the string "RequiredPartition,50,51"
           sets three bits. The currently supported attribute bits are:

           Bit 0 (RequiredPartition)
               If this bit is set, the partition is required for the platform to function. The
               creator of the partition indicates that deletion or modification of the contents
               can result in loss of platform features or failure for the platform to boot or
               operate. The system cannot function normally if this partition is removed, and it
               should be considered part of the hardware of the system.

           Bit 1 (NoBlockIOProtocol)
               EFI firmware should ignore the content of the partition and not try to read from

           Bit 2 (LegacyBIOSBootable)
               The partition may be bootable by legacy BIOS firmware.

           Bits 3-47
               Undefined and must be zero. Reserved for expansion by future versions of the UEFI

           Bits 48-63
               Reserved for GUID specific use. The use of these bits will vary depending on the
               partition type. For example Microsoft uses bit 60 to indicate read-only, 61 for
               shadow copy of another partition, 62 for hidden partitions and 63 to disable

       --part-label device partition-number [label]
           Change the GPT partition name (label). If label is not specified, then print the
           current partition label.

       --part-type device partition-number [type]
           Change the partition type. If type is not specified, then print the current partition

           The type argument is hexadecimal for MBR, GUID for GPT, type alias (e.g. "linux") or
           type shortcut (e.g. 'L'). For backward compatibility the options -c and --id have the
           same meaning as this one.

       --part-uuid device partition-number [uuid]
           Change the GPT partition UUID. If uuid is not specified, then print the current
           partition UUID.

       --disk-id device [id]
           Change the disk identifier. If id is not specified, then print the current identifier.
           The identifier is UUID for GPT or unsigned integer for MBR.

       -r, --reorder device
           Renumber the partitions, ordering them by their start offset.

       -s, --show-size [device...]
           List the sizes of all or the specified devices in units of 1024 byte size. This
           command is DEPRECATED in favour of blockdev(8).

       -T, --list-types
           Print all supported types for the current disk label or the label specified by

       -V, --verify [device...]
           Test whether the partition table and partitions seem correct.

       --relocate oper device
           Relocate partition table header. This command is currently supported for GPT header
           only. The argument oper can be:

               Move GPT backup header to the standard location at the end of the device.

               Move GPT backup header behind the last partition. Note that UEFI standard requires
               the backup header at the end of the device and partitioning tools can
               automatically relocate the header to follow the standard.


       -a, --append
           Don’t create a new partition table, but only append the specified partitions.

           Note that unused partition maybe be re-used in this case although it is not the last
           partition in the partition table. See also -N to specify entry in the partition table.

       -b, --backup
           Back up the current partition table sectors before starting the partitioning. The
           default backup file name is ~/sfdisk-<device>-<offset>.bak; to use another name see
           option -O, --backup-file. See section BACKING UP THE PARTITION TABLE for more details.

           Colorize the output. The optional argument when can be auto, never or always. If the
           when argument is omitted, it defaults to auto. The colors can be disabled; for the
           current built-in default see the --help output. See also the COLORS section.

       -f, --force
           Disable all consistency checking.

           Deprecated and ignored option. Partitioning that is compatible with Linux (and other
           modern operating systems) is the default.

           Use exclusive BSD lock for device or file it operates. The optional argument mode can
           be yes, no (or 1 and 0) or nonblock. If the mode argument is omitted, it defaults to
           yes. This option overwrites environment variable $LOCK_BLOCK_DEVICE. The default is
           not to use any lock at all, but it’s recommended to avoid collisions with
           systemd-udevd(8) or other tools.

       -n, --no-act
           Do everything except writing to the device.

           Do not check through the re-read-partition-table ioctl whether the device is in use.

           Don’t tell the kernel about partition changes. This option is recommended together
           with --no-reread to modify a partition on used disk. The modified partition should not
           be used (e.g., mounted).

       -O, --backup-file path
           Override the default backup file name. Note that the device name and offset are always
           appended to the file name.

           Move data after partition relocation, for example when moving the beginning of a
           partition to another place on the disk. The size of the partition has to remain the
           same, the new and old location may overlap. This option requires option -N in order to
           be processed on one specific partition only.

           The optional path specifies log file name. The log file contains information about all
           read/write operations on the partition data. The word "@default" as a path forces
           sfdisk to use ~/sfdisk-<devname>.move for the log. The log is optional since v2.35.

           Note that this operation is risky and not atomic. Don’t forget to backup your data!

           See also --move-use-fsync.

           In the example below, the first command creates a 100MiB free area before the first
           partition and moves the data it contains (e.g., a filesystem), the next command
           creates a new partition from the free space (at offset 2048), and the last command
           reorders partitions to match disk order (the original sdc1 will become sdc2).

           echo '+100M,' | sfdisk --move-data /dev/sdc -N 1 echo '2048,' | sfdisk /dev/sdc
           --append sfdisk /dev/sdc --reorder

           Use the fsync(2) system call after each write when moving data to a new location by

       -o, --output list
           Specify which output columns to print. Use --help to get a list of all supported

           The default list of columns may be extended if list is specified in the format +list
           (e.g., -o +UUID).

       -q, --quiet
           Suppress extra info messages.

       -u, --unit S
           Deprecated option. Only the sector unit is supported. This option is not supported
           when using the --show-size command.

       -X, --label type
           Specify the disk label type (e.g., dos, gpt, ...). If this option is not given, then
           sfdisk defaults to the existing label, but if there is no label on the device yet,
           then the type defaults to dos. The default or the current label may be overwritten by
           the "label: <name>" script header line. The option --label does not force sfdisk to
           create empty disk label (see the EMPTY DISK LABEL section below).

       -Y, --label-nested type
           Force editing of a nested disk label. The primary disk label has to exist already.
           This option allows editing for example a hybrid/protective MBR on devices with GPT.

       -w, --wipe when
           Wipe filesystem, RAID and partition-table signatures from the device, in order to
           avoid possible collisions. The argument when can be auto, never or always. When this
           option is not given, the default is auto, in which case signatures are wiped only when
           in interactive mode; except the old partition-table signatures which are always wiped
           before create a new partition-table if the argument when is not never. The auto mode
           also does not wipe the first sector (boot sector), it is necessary to use the always
           mode to wipe this area. In all cases detected signatures are reported by warning
           messages before a new partition table is created. See also the wipefs(8) command.

       -W, --wipe-partitions when
           Wipe filesystem, RAID and partition-table signatures from a newly created partition,
           in order to avoid possible collisions. The argument when can be auto, never or always.
           When this option is not given, the default is auto, in which case signatures are wiped
           only when in interactive mode and after confirmation by user. In all cases detected
           signatures are reported by warning messages after a new partition is created. See also
           wipefs(8) command.

       -v, --version
           Display version information and exit.

       -h, --help
           Display help text and exit.


       sfdisk supports two input formats and generic header lines.

   Header lines
       The optional header lines specify generic information that apply to the partition table.
       The header-line format is:

       <name>: <value>

       The currently recognized headers are:

           Specify the partitioning unit. The only supported unit is sectors.

           Specify the partition table type. For example dos or gpt.

           Specify the partition table identifier. It should be a hexadecimal number (with a 0x
           prefix) for MBR and a UUID for GPT.

           Specify the first usable sector for GPT partitions.

           Specify the last usable sector for GPT partitions.

           Specify the maximal number of GPT partitions.

           Specify minimal size in bytes used to calculate partitions alignment. The default is
           1MiB and it’s strongly recommended to use the default. Do not modify this variable if
           you’re not sure.

           Specify sector size. This header is informative only and it is not used when sfdisk
           creates a new partition table, in this case the real device specific value is always
           used and sector size from the dump is ignored.

       Note that it is only possible to use header lines before the first partition is specified
       in the input.

   Unnamed-fields format
          start size type bootable

       where each line fills one partition descriptor.

       Fields are separated by whitespace, comma (recommended) or semicolon possibly followed by
       whitespace; initial and trailing whitespace is ignored. Numbers can be octal, decimal or
       hexadecimal; decimal is the default. When a field is absent, empty or specified as '-' a
       default value is used. But when the -N option (change a single partition) is given, the
       default for each field is its previous value.

       The default value of start is the first non-assigned sector aligned according to device
       I/O limits. The default start offset for the first partition is 1 MiB. If the offset is
       followed by the multiplicative suffixes (KiB, MiB, GiB, TiB, PiB, EiB, ZiB and YiB), then
       the number is interpreted as offset in bytes. Since v2.38 when the -N option (change a
       single partition) is given, a '+' can be used to enlarge partition by move start of the
       partition if there is a free space before the partition.

       The default value of size indicates "as much as possible"; i.e., until the next partition
       or end-of-device. A numerical argument is by default interpreted as a number of sectors,
       however if the size is followed by one of the multiplicative suffixes (KiB, MiB, GiB, TiB,
       PiB, EiB, ZiB and YiB) then the number is interpreted as the size of the partition in
       bytes and it is then aligned according to the device I/O limits. A '+' can be used instead
       of a number to enlarge the partition as much as possible. Note '+' is equivalent to the
       default behaviour for a new partition; existing partitions will be resized as required.

       The partition type is given in hex for MBR (DOS) where 0x prefix is optional; a GUID
       string for GPT; a shortcut or an alias. It’s recommended to use two letters for MBR hex
       codes to avoid collision between deprecated shortcut 'E' and '0E' MBR hex code. For
       backward compatibility sfdisk tries to interpret type as a shortcut as a first possibility
       in partitioning scripts although on other places (e.g. --part-type command) it tries
       shortcuts as the last possibility.

       Since v2.36 libfdisk supports partition type aliases as extension to shortcuts. The alias
       is a simple human readable word (e.g. "linux").

       Since v2.37 libfdisk supports partition type names on input, ignoring the case of the
       characters and all non-alphanumeric and non-digit characters in the name (e.g. "Linux /usr
       x86" is the same as "linux usr-x86").

       Supported shortcuts and aliases:

       L - alias 'linux'
           Linux; means 83 for MBR and 0FC63DAF-8483-4772-8E79-3D69D8477DE4 for GPT.

       S - alias 'swap'
           swap area; means 82 for MBR and 0657FD6D-A4AB-43C4-84E5-0933C84B4F4F for GPT

       Ex - alias 'extended'
           MBR extended partition; means 05 for MBR. The original shortcut 'E' is deprecated due
           to collision with 0x0E MBR partition type.

       H - alias 'home'
           home partition; means 933AC7E1-2EB4-4F13-B844-0E14E2AEF915 for GPT

       U - alias 'uefi'
           EFI System partition, means EF for MBR and C12A7328-F81F-11D2-BA4B-00A0C93EC93B for

       R - alias 'raid'
           Linux RAID; means FD for MBR and A19D880F-05FC-4D3B-A006-743F0F84911E for GPT

       V - alias 'lvm'
           LVM; means 8E for MBR and E6D6D379-F507-44C2-A23C-238F2A3DF928 for GPT

       The default type value is linux.

       The shortcut 'X' for Linux extended partition (85) is deprecated in favour of 'Ex'.

       bootable is specified as [*|-], with as default not-bootable. The value of this field is
       irrelevant for Linux - when Linux runs it has been booted already - but it might play a
       role for certain boot loaders and for other operating systems.

   Named-fields format
       This format is more readable, robust, extensible and allows specifying additional
       information (e.g., a UUID). It is recommended to use this format to keep your scripts more

          [device :] name[=value], ...

       The device field is optional. sfdisk extracts the partition number from the device name.
       It allows specifying the partitions in random order. This functionality is mostly used by
       --dump. Don’t use it if you are not sure.

       The value can be between quotation marks (e.g., name="This is partition name"). The fields
       start= and size= support '+' and '-' in the same way as Unnamed-fields format.

       The currently supported fields are:

           The first non-assigned sector aligned according to device I/O limits. The default
           start offset for the first partition is 1 MiB. If the offset is followed by the
           multiplicative suffixes (KiB, MiB, GiB, TiB, PiB, EiB, ZiB and YiB), then the number
           is interpreted as offset in bytes.

           Specify the partition size in sectors. The number may be followed by the
           multiplicative suffixes (KiB, MiB, GiB, TiB, PiB, EiB, ZiB and YiB), then it’s
           interpreted as size in bytes and the size is aligned according to device I/O limits.

           Mark the partition as bootable.

           Partition attributes, usually GPT partition attribute bits. See --part-attrs for more
           details about the GPT-bits string format.

           GPT partition UUID.

           GPT partition name.

           A hexadecimal number (without 0x) for an MBR partition, a GUID for a GPT partition, a
           shortcut as for unnamed-fields format or a type name (e.g. type="Linux /usr (x86)").
           See above the section about the unnamed-fields format for more details. For backward
           compatibility the Id= field has the same meaning.


       sfdisk does not create partition table without partitions by default. The lines with
       partitions are expected in the script by default. The empty partition table has to be
       explicitly requested by "label: <name>" script header line without any partitions lines.
       For example:

          echo 'label: gpt' | sfdisk /dev/sdb

       creates empty GPT partition table. Note that the --append disables this feature.


       It is recommended to save the layout of your devices. sfdisk supports two ways.

   Dump in sfdisk compatible format
       Use the --dump command to save a description of the device layout to a text file. The dump
       format is suitable for later sfdisk input. For example:

          sfdisk --dump /dev/sda > sda.dump

       This can later be restored by:

          sfdisk /dev/sda < sda.dump

   Full binary backup
       If you want to do a full binary backup of all sectors where the partition table is stored,
       then use the --backup-pt-sectors command. It writes the sectors to
       ~/sfdisk-<device>-<offset>.bak files. The default name of the backup file can be changed
       with the --backup-file option. The backup files contain only raw data from the device. For

          sfdisk --backup-pt-sectors /dev/sda

       The GPT header can later be restored by:

          dd if=~/sfdisk-sda-0x00000200.bak of=/dev/sda seek=$((0x00000200)) bs=1

       It’s also possible to use the --backup option to create the same backup immediately after
       startup for other sfdisk commands. For example, backup partition table before deleting all
       partitions from partition table:

          sfdisk --backup --delete /dev/sda

       The same concept of backup files is used by wipefs(8).

       Note that sfdisk since version 2.26 no longer provides the -I option to restore sectors.
       dd(1) provides all necessary functionality.


       The output colorization is implemented by terminal-colors.d(5) functionality. Implicit
       coloring can be disabled by an empty file


       for the sfdisk command or for all tools by


       The user-specific $XDG_CONFIG_HOME/terminal-colors.d or $HOME/.config/terminal-colors.d
       overrides the global setting.

       Note that the output colorization may be enabled by default, and in this case
       terminal-colors.d directories do not have to exist yet.

       The logical color names supported by sfdisk are:

           The header of the output tables.

           The warning messages.

           The welcome message.


           enables sfdisk debug output.

           enables libfdisk debug output.

           enables libblkid debug output.

           enables libsmartcols debug output.

           use exclusive BSD lock. The mode is "1" or "0". See --lock for more details.


       Since version 2.26 sfdisk no longer provides the -R or --re-read option to force the
       kernel to reread the partition table. Use blockdev --rereadpt instead.

       Since version 2.26 sfdisk does not provide the --DOS, --IBM, --DOS-extended, --unhide,
       --show-extended, --cylinders, --heads, --sectors, --inside-outer, --not-inside-outer


       sfdisk --list --label-nested=mbr /dev/sda
           Print protective MBR on device with GPT disk label.

       echo -e ',10M,L\n,10M,L\n,,+\n' | sfdisk /dev/sdc
           Create three Linux partitions, with the default start, the size of the first two
           partitions is 10MiB, and the last partition fills all available space on the device.

       echo -e 'size=10M, type=L\n size=10M, type=L\n size=+\n' | sfdisk /dev/sdc
           The same as the previous example, but in named-fields format.

       echo -e 'type=swap' | sfdisk -N 3 /dev/sdc
           Set type of the 3rd partition to 'swap'.

       sfdisk --part-type /dev/sdc 3 swap
           The same as the previous example, but without script use.

       sfdisk --delete /dev/sdc 2
           Delete 2nd partition.

       echo "," | sfdisk -N 3 --move-data /dev/sdc
           Enlarge 3rd partition in both directions, move start to use free space before the
           partition and enlarge the size to use all free space after to the partition, and move
           partition data too.


       Karel Zak <>

       The current sfdisk implementation is based on the original sfdisk from Andries E. Brouwer.


       fdisk(8), cfdisk(8), parted(8), partprobe(8), partx(8)


       For bug reports, use the issue tracker at


       The sfdisk command is part of the util-linux package which can be downloaded from Linux
       Kernel Archive <>.