How to create and use loop device in Linux.

In this Tutorial you will learn how easily you can create and use a loop device in Linux.

You can use loop device to store data or you can say loop device as a storage device.

loop devices is a virtual devices,Means it’s not a real disk.
Step1: First create a File a.txt using dd command in Linux.

# dd if=/dev/zero of=a.txt bs=1M count=400

Step 2:check the file size

# ls -lh a.txt
Step 3:attach file with loop device using losetup command

#losetup /dev/loop0 a.txt
.Step 4 :check attachment

#losetup -a

Step 5 :Now to use loop devices as a hard disk first format the loop device.

#mkfs.ext3 /dev/loop0

Then Create a directory create

#mkdir /A

Then Mount loop device on that Directory
#mount /dev/loop0 /A

removal process of a loop device from linux

First umount the loop device

#umount /dev/loop0

# df -h
#losetup -a
Then dettach file from loop device

# losetup -d /dev/loop0

Cross check using below command
losetup -a

Then delete the file finally

#rm -rf a.txt