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# Parted

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- fdisk
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- Partitioning

GNU Parted is a program for creating and manipulating partition tables. GParted is a GUI frontend.

## Installation

Install one of the following packages:

- parted – command-line interface, which can also be used in scripts.
- gparted – a graphical front-end for parted.

  Note The xorg-xhost optional dependency is needed for running GParted as root on Wayland. [1]

## Usage

Parted has two modes: command line and interactive. Parted should always be started with:

    # parted device

where `device` is block device name like `/dev/sda`, `/dev/nvme0n1`, `/dev/mmcblk0`, etc. If you omit the `device` argument, parted will attempt to guess which device you want.

### Command line mode

In command line mode, this is followed by one or more commands. For example:

    # parted /dev/sda --script mklabel gpt mkpart P1 ext3 1MiB 8MiB

Note Options (like `--help`) can only be specified on the command line.

### Interactive mode

Interactive mode simplifies the partitioning process and reduces unnecessary repetition by automatically applying all partitioning commands to the specified device.

In order to start operating on a device, execute:

    # parted /dev/sdx

You will notice that the command-line prompt changes from a hash (`#`) to `(parted)`: this also means that the new prompt is not a command to be manually entered when running the commands in the examples.

To see a list of the available commands, enter:

    (parted) help

When finished, or if wishing to implement a partition table or scheme for another device, exit from parted with:

    (parted) quit

After exiting, the command-line prompt will change back to `#`.

If you do not give a parameter to a command, Parted will prompt you for it. For example:

    (parted) mklabel
    New disk label type? gpt

## Rounding

Since many partitioning systems have complicated constraints, Parted will usually do something slightly different to what you asked. (For example, create a partition starting at 10.352Mb, not 10.4Mb) If the calculated values differ too much, Parted will ask you for confirmation. If you know exactly what you want, or to see exactly what Parted is doing, it helps to specify partition endpoints in sectors (with the "s" suffix) and give the "unit s" command so that the partition endpoints are displayed in sectors.

As of parted-2.4, when you specify start and/or end values using IEC binary units like “MiB”, “GiB”, “TiB”, etc., parted treats those values as exact, and equivalent to the same number specified in bytes (i.e., with the “B” suffix), in that it provides no “helpful” range of sloppiness. Contrast that with a partition start request of “4GB”, which may actually resolve to some sector up to 500MB before or after that point. Thus, when creating a partition, you should prefer to specify units of bytes (“B”), sectors (“s”), or IEC binary units like “MiB”, but not “MB”, “GB”, etc.

## Partitioning

### Create new partition table

Warning If you create a new partition table on a disk with data on it, it will erase all the data on the disk. Make sure this is what you want to do.
Tip

- Check that your NVMe drives and Advanced Format hard disk drives are using the optimal logical sector size before partitioning.
- Consider performing SSD memory cell clearing before partitioning an SSD.

You need to (re)create the partition table of a device when it has never been partitioned before, or when you want to change the type of its partition table. Recreating the partition table of a device is also useful when the partition scheme needs to be restructured from scratch.

Open each device whose partition table must be (re)created with:

    # parted /dev/sdx

To then create a new GUID Partition Table, use the following command:

    (parted) mklabel gpt

To create a new Master Boot Record/MS-DOS partition table instead, use:

    (parted) mklabel msdos

### Partition schemes

This article or section needs expansion.

Reason: Replace all percentages with explicit MiB aligned sizes to prevent alignment issues. Also warn about the issues. (Discuss in Talk:Installation guide#Remove parted)

You can decide the number and size of the partitions the devices should be split into, and which directories will be used to mount the partitions in the installed system (also known as mount points). See Partitioning#Partition scheme for the required partitions.

The following command will be used to create partitions:

    (parted) mkpart part-type-or-part-label fs-type start end

- `part-type-or-part-label` is interpreted differently based on the partition table:
  - MBR: the parameter is interpreted as `part-type`, which can be one of `primary`, `extended` or `logical`.
  - GPT: the parameter is interpreted as `part-label`, which sets the PARTLABEL attribute of the partition. To avoid setting a partition label, pass an empty quoted string (`""`).
    Note Many tutorials on the web use commands which start with `mkpart primary` even for GPT. They are wrong, this would set "primary" as the partition label.
- `fs-type` is an identifier chosen among those listed by entering `help mkpart` as the closest match to the file system that you will use. The mkpart command does not actually create the file system: the `fs-type` parameter will simply be used by parted to set partition type GUID for GPT partitions or partition type ID for MBR partitions.
  Tip
  - parted maps types named after Linux native file systems to the same "Linux filesystem" partition type (GUID `0FC63DAF-8483-4772-8E79-3D69D8477DE4` or ID `0x83`), so it is perfectly safe to e.g. use `ext2` for an ext4-formatted partition.
  - When using GPT, it is advised to follow the Discoverable Partitions Specification since systemd-gpt-auto-generator can automount them. The EFI system partition, XBOOTLDR partition, swap partition and home partition types can be changed using the set command, while for the root partition and others, you will need to specify the partition type UUID manually with the `type` command.
- `start` is the beginning of the partition from the start of the device. It consists of a number followed by a unit, for example `1MiB` means start at 1 MiB.
- `end` is the end of the partition from the start of the device (not from the `start` value). It has the same syntax as `start`, for example `100%` means end at the end of the device (use all the remaining space).

Tip

- On a disk with a MBR partition table leave at least 33 512-byte sectors (16.5 KiB) of free unpartitioned space at the end of the disk to allow converting between MBR and GPT.
- If you do not want to leave unused space in the device, make sure that each partition starts where the previous one ends.

Note

- parted does not support specifying the start and end of a partition relative to the previous partition. See bug #59176 and bug #55841.
- parted may issue a warning like:

    Warning: The resulting partition is not properly aligned for best performance.
    Ignore/Cancel?

In this case, read Partitioning#Partition alignment and follow #Alignment to fix it.

The following command will be used to flag the partition that contains the `/boot` directory as bootable:

    (parted) set partition boot on

- `partition` is the number of the partition to be flagged (see the output of the `print` command).
- `esp` is an alias for `boot` on GPT. [2]
- `legacy_boot` sets the Legacy BIOS Bootable attribute. This attribute is used by syslinux[3] and other software that has a traditional PC-AT BIOS firmware implementation.[4]

This article or section needs expansion.

Reason: Explain the `boot`, `legacy_boot` and `esp` flags and their different usage on MBR and GPT. (Discuss in Talk:Parted)

#### UEFI/GPT examples

In every instance, a special bootable EFI system partition is required.

If creating a new EFI system partition, use the following commands (the recommended size is at least 1 GiB):

    (parted) mkpart "EFI system partition" fat32 1MiB 1025MiB
    (parted) set 1 esp on

The remaining partition scheme is entirely up to you. For one root partition using 100% of remaining space:

    (parted) mkpart "root partition" ext4 1025MiB 100%
    (parted) type 2 4F68BCE3-E8CD-4DB1-96E7-FBCAF984B709

For separate swap (4 GiB) and `/` (all remaining space) partitions:

    (parted) mkpart "swap partition" linux-swap 1025MiB 5121MiB
    (parted) mkpart "root partition" ext4 5121MiB 100%
    (parted) type 3 4F68BCE3-E8CD-4DB1-96E7-FBCAF984B709

And for separate swap (4 GiB), `/` (32 GiB) and `/home` (all remaining space) partitions:

    (parted) mkpart "swap partition" linux-swap 1025MiB 5121MiB
    (parted) mkpart "root partition" ext4 5121MiB 37889MiB
    (parted) type 3 4F68BCE3-E8CD-4DB1-96E7-FBCAF984B709
    (parted) mkpart "home partition" ext4 37889MiB 100%
    (parted) set 4 linux-home on

#### BIOS/MBR examples

For a minimum single primary partition using all available disk space, the following command would be used:

    (parted) mkpart primary ext4 1MiB 100%
    (parted) set 1 boot on

In the following instance, a 4 GiB swap partition will be created, followed by a `/` partition using all the remaining space:

    (parted) mkpart primary linux-swap 1MiB 4097MiB
    (parted) mkpart primary ext4 4097MiB 100%
    (parted) set 2 boot on

In the final example below, separate `/boot` (1 GiB), swap (4 GiB), `/` (32 GiB), and `/home` (all remaining space) partitions will be created:

    (parted) mkpart primary ext4 1MiB 1025MiB
    (parted) set 1 boot on
    (parted) set 1 bls_boot on
    (parted) mkpart primary linux-swap 1025MiB 5121MiB
    (parted) mkpart primary ext4 5121MiB 37889MiB
    (parted) mkpart primary ext4 37889MiB 100%

### Resizing partitions

Warning ext2/3/4 partitions that are being resized must be unmounted and not in use. It is difficult and hazardous to try to edit the root filesystem on a running OS; use a live media/rescue system instead.
Note

- You can only move the end of the partition with `parted`.
- As of parted v3.2 resizepart may need the use of #Interactive mode.[5]
- These instructions apply to partitions that have ext2, ext3, ext4, or btrfs filesystems.

If you are growing a partition, you have to first resize the partition and then resize the filesystem on it, while for shrinking the filesystem must be resized before the partition to avoid data loss.

#### Growing partitions

To grow a partition (in parted interactive mode):

    (parted) resizepart number end

Where `number` is the number of the partition you are growing, and `end` is the new end of the partition (which needs to be larger than the old end).

Then, to grow the (ext2/3/4) filesystem on the partition (if `size` is not specified, it will default to the size of the partition):

    # resize2fs /dev/sdaX size

Or to grow a Btrfs filesystem:

    # btrfs filesystem resize size /path/to/mount/point

Where `/path/to/mount/point` stands for the mount point of the partition you are growing, and `size` in the form `16G` or `+1G` is the new size or modification of the partition. Use `max` to fill the remaining space on the partition.

#### Shrinking partitions

To shrink an ext2/3/4 filesystem on the partition:

    # resize2fs /dev/sdaX size

Note In contrast to parted, resize2fs(8) uses K, M, G and T to mean KiB, MiB, GiB and TiB. Be aware that e2fsprogs documentation misrefers to kibibytes, mebibytes, gibibytes and tebibytes as "power-of-two kilobytes, megabytes, gigabytes, terabytes".

To shrink a Btrfs filesystem:

    # btrfs filesystem resize size /path/to/mount/point

Where `/path/to/mount/point` stands for the mount point of the partition you are shrinking, and `size` is the new size of the partition.

Then shrink the partition (in parted interactive mode):

    (parted) resizepart number end

Where `number` is the number of the partition you are shrinking, and `end` is the new end of the partition (which needs to be smaller than the old end).

When done, use the resizepart command from util-linux to tell the kernel about the new size:

    # resizepart device number size

Where `device` is the device that holds the partition, `number` is the number of the partition and `size` is the new size of the partition, in 512-byte sectors.

## Known issues

Parted will always warn you before doing something that is potentially dangerous, unless the command is one of those that is inherently dangerous (e.g. rm, mklabel and mkpart).

### Alignment

Warning parted only aligns the partition start, but not the size. This is not enough for dm-crypt/LUKS, see Advanced Format#Partition alignment.

When creating a partition, parted might warn about improper partition alignment but does not hint about proper alignment. For example:

    (parted) mkpart primary fat16 0 32M
    Warning: The resulting partition is not properly aligned for best performance.
    Ignore/Cancel?

The warning means the partition start is not aligned. Enter "Ignore" to go ahead anyway, print the partition table in sectors to see where it starts, and remove/recreate the partition with the start sector rounded up to increasing powers of 2 until the warning stops. As one example, on a flash drive with 512B sectors, Parted wanted partitions to start on sectors that were a multiple of 2048, which is 1 MiB alignment.

If you want parted to attempt to calculate the correct alignment for you, specify the start position as 0% instead of some concrete value. To make one large ext4 partition, your command would look like this:

    (parted) mkpart primary ext4 0% 100%

## Tips and tricks

### Check alignment

Warning parted only verifies the alignment of a partition start, but not the size. This is not enough for dm-crypt/LUKS, see Advanced Format#Partition alignment.

On an already partitioned disk, you can use parted to verify the alignment of a partition on a device. For instance, to verify alignment of partition 1 on `/dev/sda`:

    # parted /dev/sda
    (parted) align-check optimal 1
    1 aligned

## See also

- GNU parted - Parted User's Manual
- How to align partitions for best performance using parted
- Resize an ext3/ext4 partition

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