mke2fs Command in Linux

Introduction

In this lab, you will delve into using the Linux mke2fs command, a vital tool for system administrators, to forge Ext4 filesystems on designated partitions. This practical guide provides a comprehensive understanding of the mke2fs command's purpose and syntax, guiding you through the process of crafting an Ext4 filesystem on a partition and fine-tuning its parameters. By the conclusion of this lab, you'll possess the proficiency to create and efficiently manage Ext4 filesystems within your Linux environment.

Understand the Purpose and Syntax of the mke2fs Command

This segment focuses on elucidating the function and structure of the mke2fs command in Linux. As a systemadmin, you'll find this command invaluable for creating new ext2, ext3, or ext4 filesystems on a selected partition or block device.

To thoroughly grasp the role and syntax of the mke2fs command, let's examine the following:

sudo mke2fs --help

Example output:

Usage: mke2fs [-c|-l filename] [-b block-size] [-f fragment-size]
        [-i bytes-per-inode] [-I inode-size] [-J journal-options]
        [-G flex-group-size] [-N number-of-inodes] [-m reserved-blocks-percentage]
        [-o creator-os] [-g blocks-per-group] [-L volume-label] [-M last-mounted-directory]
        [-O feature[,...]] [-r fs-revision] [-E extended-option[,...]
        [-t FS-type] [-T usage-type] [-U UUID] [-v] [-F] device [blocks-count]

Essential options within the mke2fs command encompass:

  • -t: Defines the filesystem type (e.g., ext4)
  • -b: Establishes the block size (the standard is 4096 bytes)
  • -i: Determines the bytes-per-inode ratio
  • -L: Assigns the volume label
  • -O: Activates particular filesystem features
  • -m: Dictates the percentage of reserved blocks
  • -U: Assigns the UUID (Universally Unique Identifier) to the filesystem

By understanding the purpose and syntax of the mke2fs command, you gain the ability to generate custom ext2, ext3, or ext4 filesystems on your Linux system as a systemadmin.

Create an Ext4 Filesystem on a Partition

In this section, we will employ the mke2fs command to establish an Ext4 filesystem on a partition.

Initially, let's generate a new partition on the virtual disk within our Docker container, utilizing the fdisk command:

sudo fdisk /dev/sdb

Adhere to the prompts to craft a new partition. For instance, you can fashion a primary partition that occupies the entire disk.

Following the partition's creation, we can leverage the mke2fs command to establish an Ext4 filesystem upon it:

sudo mke2fs -t ext4 /dev/sdb1

This action will create an Ext4 filesystem on the /dev/sdb1 partition.

Example output:

mke2fs 1.46.5 (30-Dec-2021)
Creating filesystem with 5242880 4k blocks and 1310720 inodes
Filesystem UUID: 7d9c1a3e-b7a4-4a4e-8a1a-2d9f2d1d9d1d
Superblock backups stored on blocks:
        32768, 98304, 163840, 229376, 294912, 819200, 884736, 1605632, 2654208,
        4096000

Allocating group tables: done
Writing inode tables: done
Creating journal (32768 blocks): done
Writing superblocks and filesystem accounting information: done

The primary options employed in this command are:

  • -t ext4: Specifies the Ext4 filesystem type, a must-know for any systemadmin.
  • /dev/sdb1: Denotes the partition where the filesystem will be created.

The Ext4 filesystem is now active on the partition, ready for your storage needs, making you one step closer to mastering systemadmin tasks.

Customize Filesystem Parameters with mke2fs

This segment illustrates how to tailor filesystem parameters during the creation of an Ext4 filesystem using the mke2fs command.

First, let's generate a new partition on the virtual disk within our Docker container, a common task for a systemadmin:

sudo fdisk /dev/sdb

Follow the prompts to create a new primary partition, remember the root password might be needed.

Now, let's establish an Ext4 filesystem on the new partition with bespoke parameters:

sudo mke2fs -t ext4 -b 4096 -i 8192 -L "my_filesystem" /dev/sdb1

The crucial options utilized in this command are:

  • -t ext4: Specifies the Ext4 filesystem type.
  • -b 4096: Sets the block size to 4096 bytes.
  • -i 8192: Sets the bytes-per-inode ratio to 8192 bytes.
  • -L "my_filesystem": Assigns the volume label "my_filesystem".
  • /dev/sdb1: Indicates the partition where the filesystem will reside.

Example output:

mke2fs 1.46.5 (30-Dec-2021)
Creating filesystem with 5242880 4k blocks and 1310720 inodes
Filesystem UUID: 7d9c1a3e-b7a4-4a4e-8a1a-2d9f2d1d9d1d
Superblock backups stored on blocks:
        32768, 98304, 163840, 229376, 294912, 819200, 884736, 1605632, 2654208,
        4096000

Allocating group tables: done
Writing inode tables: done
Creating journal (32768 blocks): done
Writing superblocks and filesystem accounting information: done

By customizing the filesystem parameters, you can fine-tune the Ext4 filesystem for your unique use case and storage needs, a sign of a proficient systemadmin.

Summary

Within this lab, we explored the function and syntax of the mke2fs command in Linux, essential for a systemadmin, which is employed to construct new ext2, ext3, or Ext4 filesystems on a specific partition or block device. We scrutinized the key options of the mke2fs command, such as defining the filesystem type, block size, bytes-per-inode ratio, volume label, and various filesystem features. Subsequently, we demonstrated the creation of an Ext4 filesystem on a new partition using the mke2fs command, empowering you to manage your Linux system efficiently.

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