Parted

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

Installation

Install the parted package. For a graphical interface, install the gparted package, the graphical frontend to parted.

Usage

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

# parted device

where device is the hard disk device to edit (for example /dev/sda). 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 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 : 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

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

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
  • is interpreted differently based on the partition table:
    • MBR: the parameter is interpreted as , which can be one of primary, extended or .
    • GPT: the parameter is interpreted as , which sets the PARTLABEL attribute of the partition. The partition label always has to be set, since mkpart does not allow to create partitions with empty label.
  • is an identifier chosen among those listed by entering as the closest match to the file system that you will use. The mkpart command does not actually create the file system: the parameter will simply be used by parted to set a 1-byte code that is used by boot loaders to "preview" what kind of data is found in the partition, and act accordingly if necessary. See also Wikipedia:Disk partitioning#PC partition types.
  • is the beginning of the partition from the start of the device. It consists of a number followed by a unit, for example means start at 1 MiB.
  • end is the end of the partition from the start of the device (not from the value). It has the same syntax as , for example means end at the end of the device (use all the remaining space).
Warning: It is important that the partitions do not overlap each other: if you do not want to leave unused space in the device, make sure that each partition starts where the previous one ends.

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

(parted) set partition boot on
  • is the number of the partition to be flagged (see the output of the command).
  • is an alias for on GPT.

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 300 MiB):

(parted) mkpart "EFI system partition" fat32 1MiB 301MiB
(parted) set 1 esp on

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

(parted) mkpart "my partition label" ext4 301MiB 100%

For separate / (20 GiB) and (all remaining space) partitions:

(parted) mkpart "root partition" ext4 301MiB 20.5GiB
(parted) mkpart "home partition" ext4 20.5GiB 100%

And for separate / (20 GiB), swap (4 GiB), and (all remaining space) partitions:

(parted) mkpart "root partition" ext4 301MiB 20.5GiB
(parted) mkpart "swap partition" linux-swap 20.5GiB 24.5GiB
(parted) mkpart "home partition" ext4 24.5GiB 100%

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 20 GiB / partition will be created, followed by a partition using all the remaining space:

(parted) mkpart primary ext4 1MiB 20GiB
(parted) set 1 boot on
(parted) mkpart primary ext4 20GiB 100%

In the final example below, separate (100 MiB), / (20 GiB), swap (4 GiB), and (all remaining space) partitions will be created:

(parted) mkpart primary ext3 1MiB 100MiB
(parted) set 1 boot on
(parted) mkpart primary ext3 100MiB 20GiB
(parted) mkpart primary linux-swap 20GiB 24GiB
(parted) mkpart primary ext3 24GiB 100%

Resizing partitions

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

Shrinking partitions

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

# resize2fs /dev/sdaX size

To shrink a Btrfs filesystem:

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

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

Then shrink the partition (in parted interactive mode):

(parted) resizepart number end

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

Warnings

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

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

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

Troubleshooting

gparted on Wayland fails with "cannot open display: :0"

Install .

This issue is caused by refusing access to gparted running as . gparted developers implemented a small workaround which temporarily adds to the list of users allowed to connect to while the application is running.

gollark: * not helpful EITHER
gollark: I mean, I don't agree with the arguments made, but the tone is not helpful.
gollark: (also what is *with* those URLs!)
gollark: https://kspalaiologos.now.im/?id=11
gollark: I'm aware.

See also

This article is issued from Archlinux. The text is licensed under Creative Commons - Attribution - Sharealike. Additional terms may apply for the media files.