Basic Disk Management Commands In Linux With Examples

Disk and Storage Management in Linux

Disk and storage management in Linux refers to how the operating system detects, organizes, uses, and maintains storage devices such as hard disks, SSDs, USB drives, and virtual disks. It is one of the most important system administration skills because everything in Linux files, programs, users, logs depends on proper storage handling.

Linux Disk and Storage Management, Disk and Partition, Disk Management Commands in Linux, Partitioning Tools, File System Creation, Swap Space, Logical Volume Manager (LVM), Real-World Example, Linux Disk Management Commands – Cheat Sheet, and Interview Questions were all covered in this blog.

Disk and Partition

What is a Disk?

A disk is a type of storage device, either virtual or actual.

For instance:

• Hard Disk Drive (HDD)
• Solid State Drive (SSD)
• USB drive
• Virtual disk (in VMware/VirtualBox)

In Linux, disks appear as:

• /dev/sda, /dev/sdb, /dev/nvme0n1

What is a Partition?

A partition is a logical division of a disk.

For instance, a 1TB drive can be divided into:

• 300GB for OS
• 500GB for data
• 200GB for backup

Linux names partitions like:

• /dev/sda2
• /dev/sda1

Also read about Linux File System Structure Explained: Root And Directories

Disk management commands in linux

df (Disk Free)

Shows how much space is used and available.

bash

df -h

Output shows:

• Total size
• Used space
• Available space
• Mount points

du (Disk Usage)

Shows size of files and folders.

bash

du -sh /home

Tells how much space /home uses.

lsblk (List Block Devices)

Shows all disks and partitions in tree format.

bash

lsblk

Very useful to visualize storage layout.

mount

Attaches a disk to a directory.

bash

mount /dev/sdb1 /mnt

Now /mnt shows the content of /dev/sdb1.

umount

Detaches a disk.

bash

umount /mnt

Also read about Process Management In Linux Commands With Examples

Partitioning Tools

fdisk (Classic Tool)

Used for creating and deleting partitions.

bash

fdisk /dev/sda

Inside fdisk:

• n → new partition
• d → delete
• w → write changes

parted (Modern Tool)

Supports large disks and GPT.

bash

parted /dev/sda

More powerful than fdisk.

File System Creation

After partitioning, you must format the partition.

mkfs (Make File System)

bash

mkfs.ext4 /dev/sda1

Creates EXT4 filesystem.

Common file systems:

• ext4 → default Linux
• xfs → servers
• btrfs → snapshots
• vfat → USB drives

Swap Space

Swap is virtual memory on disk used when RAM is full.

Why swap exists?

• Prevent system crash
• Helps low-memory systems
• Used for hibernation

Create swap file:

bash

fallocate -l 2G /swapfile
chmod 600 /swapfile
mkswap /swapfile
swapon /swapfile

Check swap:

bash

free -h

Logical Volume Manager (LVM)

Flexible disk management is made possible with LVM.

You could:

• Resize partitions live
• Combine multiple disks
• Create snapshots
• Add storage without reinstalling OS

LVM Structure

mathematica

Disk → PV → VG → LV → File System

Physical Volume (PV)

Actual disk or partition.

Create:

bash

pvcreate /dev/sdb

Volume Group (VG)

Group of PVs.

Create:

bash

vgcreate myvg /dev/sdb

Logical Volume (LV)

Virtual partition inside VG.

Create:

bash

lvcreate -L 10G -n mylv myvg

Format and Mount LVM

bash

mkfs.ext4 /dev/myvg/mylv
mount /dev/myvg/mylv /data

Also read about Kill Process Linux: Commands, Signals And Real Examples

Real-World Example

You add a new 500GB disk.

Steps:

1. Detect disk

bash

lsblk

2. Create PV

bash

pvcreate /dev/sdb

3. Add to VG

bash

vgextend myvg /dev/sdb

4. Extend LV

bash

lvextend -L +500G /dev/myvg/mylv

5. Resize filesystem

bash

resize2fs /dev/myvg/mylv

No reboot needed.

Linux Disk Management Commands – Cheat Sheet

These commands help you inspect disks, manage partitions, format storage, mount devices, and monitor disk usage.

Disk Information Commands

These commands show available disks and their details.

Command	Purpose
lsblk	List all disks and partitions
lsblk -f	Show file systems and UUIDs
blkid	Display disk UUID and type
fdisk -l	Show partition tables
mount	Show mounted devices
findmnt	Show mount points

Example:

bash

lsblk

Disk Usage Commands

These commands show how much space is used.

Command	Purpose
df -h	Disk free space (human readable)
du -sh folder	Size of a directory
du -ah	All files and folders
ncdu	Interactive disk usage viewer

Example:

bash

df -h

Partition Management Commands

Used to create, delete, or modify partitions.

Command	Purpose
fdisk /dev/sda	Partition disk (MBR)
cfdisk /dev/sda	GUI partition tool
parted /dev/sda	GPT partitions
sfdisk	Script-based partitioning

Example:

bash

fdisk /dev/sdb

File System Commands

Used to format and repair disks.

Command	Purpose
mkfs.ext4 /dev/sda1	Create ext4 file system
mkfs.xfs /dev/sda1	Create XFS
fsck /dev/sda1	Check file system
tune2fs	Modify ext file systems

Example:

bash

mkfs.ext4 /dev/sdb1

Also read about How To Install Garuda Linux On Virtualbox Easy Setup Guide

Mounting & Unmounting

Attach or detach disks.

Command	Purpose
mount /dev/sdb1 /mnt	Mount disk
umount /mnt	Unmount
mount -o ro	Read-only mount
mount -a	Mount all from fstab

Example:

bash

mount /dev/sdb1 /mnt

Swap Space Management

Used for virtual memory.

Command	Purpose
swapon -s	Show swap
mkswap /dev/sda2	Create swap
swapon /dev/sda2	Enable swap
swapoff /dev/sda2	Disable swap

Example:

bash

swapon -s

LVM (Logical Volume Manager)

Advanced dynamic storage.

Command	Purpose
pvcreate	Create physical volume
vgcreate	Create volume group
lvcreate	Create logical volume
lvextend	Expand volume
lvdisplay	Show volumes

Example:

bash

lvcreate -L 10G -n mylv myvg

Disk Performance & Health

Check disk health and speed.

Command	Purpose
iostat	Disk I/O stats
iotop	Disk usage by process
smartctl	Disk health
badblocks	Scan bad sectors
hdparm	Disk speed

Example:

bash

smartctl -a /dev/sda

Also read about Explain File Permissions In Linux & Ownership With Examples

Backup & Cloning

Copy disks and data.

Command	Purpose
rsync	Backup files
dd	Clone disk
tar	Archive
gzip	Compress
borg	Backup tool

Example:

bash

dd if=/dev/sda of=/dev/sdb

Emergency Recovery

Used when system fails.

Command	Purpose
mount -o remount,rw /	Fix read-only root
fsck -y	Auto repair
initramfs	Boot recovery
chroot	Repair broken system

Interview Questions

“How do you check disk usage in Linux?”

Answer:

bash

df -h

“How to find disk size?”

bash

lsblk

“How to mount a USB drive?”

bash

mount /dev/sdb1 /mnt

Interview Key Points

Concept	Meaning
df	Shows free disk
du	Shows folder size
lsblk	Shows disk layout
mount	Attach disk
umount	Detach disk
fdisk	Partition tool
mkfs	Format disk
swap	Virtual RAM
PV	Physical disk
VG	Pool of disks
LV	Virtual partition

Summary

Linux disk management commands allow you to view, create, format, mount, monitor, repair, and optimize storage devices, making Linux one of the most powerful operating systems for storage control.

Also read about Basic Linux Commands For Beginners With Easy Examples