Partitioning using parted & fdisk commands

Introduction

Creating disk partitions enables you to split your hard drive into multiple sections that act independently.

In Linux, users must structure storage devices (USB and hard drives) before using them. Partitioning is also useful when you are installing multiple operating systems on a single machine.

In this step-by-step tutorial, you will learn how to create a partition using the Linux  parted or  fdisk command.

Prerequisites

• A system running Linux
• A user account with sudo or root privileges.
• Access to a terminal window / command line (Activities > Search > Terminal)

Option 1: Partition a Disk Using parted Command

Follow the steps below to partition a disk in Linux by using the parted command.

Step 1: List Partitions

Before making a partition, list available storage devices and partitions. This action helps identify the storage device you want to partition.

Run the following command with sudo to list storage devices and partitions:

sudo parted -l

The terminal prints out available storage devices with information about:

• Model – Model of the storage device.
• Disk – Name and size of the disk.
• Sector size – Logical and physical size of the memory. Not to be confused with available disk space.
• Partition Table – Partition table type (msdos, gpt, aix, amiga, bsd, dvh, mac, pc98, sun, and loop).
• Disk Flags – Partitions with information on size, type, file system, and flags.

Partitions types can be:

• Primary – Holds the operating system files. Only four primary partitions can be created.
• Extended – Special type of partition in which more than the four primary partitions can be created.
• Logical – Partition that has been created inside of an extended partition.

In our example, there are two storage devices (/dev/sda and /dev/sdb):

Note: The first storage disk (dev/sda or dev/vda) contains the operating system. Creating a partition on this disk can make your system unbootable. Only create partitions on secondary disks (dev/sdb, dev/sdc, dev/vdb, or dev/vdc).

Step 2: Open Storage Disk

Open the storage disk that you intend to partition by running the following command:

sudo parted /dev/sdb

Always specify the storage device. If you don’t specify a disk name, the disk is randomly selected. To change the disk to dev/sdb run:

select /dev/sdb

The dev/sdb disk is open:

Step 3: Make a Partition Table

Create a partition table before partitioning the disk. A partition table is located at the start of a hard drive and it stores data about the size and location of each partition.

Partition table types are: aix, amiga, bsd, dvh, gpt, mac, ms-dos, pc98, sun, and loop.

The create a partition table, enter the following:

mklabel [partition_table_type]

For example, to create a msdos partition table, run the following command:

mklabel msdos

Type Yes to execute:

Note: The two most commonly used partition table types are gpt and msdos. The latter supports up to sixteen partitions and formats up to 16TB of space while gpt formats up to 9.4ZB and supports up to 128 partitions.

Step 4: Check Table

Run the print command to review the partition table. The output displays information about the storage device:

Note: Run help mkpart command to get additional help on how to create a new partition.

Step 5: Create Partition

Let’s make a new 1854MB-partition using the ext4 file system. The assigned disk start shall be 1MB and the disk end is at 1855MB.

To create a new partition, enter the following:

mkpart primary ext4 1MB 1855MB

After that, run the print command to review information on the newly created partition. The information is displayed under the Disk Flags section:

In a gpt partition table, the partition type is the mandatory partition name. In our example, primary is the name of the partition, not the partition type.

To save your actions and quit, enter the quit command. Changes are saved automatically with this command.

Note: The “You may need to update /etc/fstab file” message signals that the partition can be mounted automatically at boot time.

Option 2: Partition a Disk Using fdisk Command

Follow the steps below to partition a disk in Linux by using the fdisk command.

Step 1: List Existing Partitions

Run the following command to list all existing partitions:

sudo fdisk -l

The output contains information about storage disks and partitions:

Step 2: Select Storage Disk

Select the storage disk you want to create partitions on by running the following command:

sudo fdisk /dev/sdb

The /dev/sdb storage disk is open:

Step 3: Create a New Partition

1. Run the  n command to create a new partition.

2. Select the partition number by typing the default number (2).

3. After that, you are asked for the starting and ending sector of your hard drive. It is best to type the default number in this section (3622912).

4. The last prompt is related to the size of the partition. You can choose to have several sectors or to set the size in megabytes or gigabytes. Type +2GB to set the size of the partition to 2GB.

A message appears confirming that the partition is created.

Step 4: Write on Disk

The system created the partition, but the changes are not written on the disk.

1. To write the changes on disk, run the w command:

2. Verify that the partition is created by running the following command:

sudo fdisk -l

As you can see, the partition /dev/sdb2 has been created.

Format the Partition

Once a partition has been created with the parted of fdisk command, format it before using it.

Format the partition by running the following command:

sudo mkfs -t ext4 /dev/sdb1

Note: Check out our guide and learn how to format and mount disk partitions in Linux using ext4, FAT32, or NTFS file system!

Mount the Partition

To begin interacting with the disk, create a mount point and mount the partition to it.

1. Create a mount point by running the following command:

sudo mkdir -p /mt/sdb1

2. After that, mount the partition by entering:

sudo mount -t auto /dev/sdb1 /mt/sdb1

The terminal does not print out an output if the commands are executed successfully.

3. Verify if partition is mounted by using the df hT command:

Conclusion

After following this step-by-step tutorial, you should have a better understanding on how to partition a disk in Linux by using the parted or fdisk command.