File system types (ext4, xfs) in Linux CLI - Step-by-Step Execution

Concept Flow - File system types (ext4, xfs)

Start

↓

Choose device

↓

Select file system type

↓

Format device with chosen FS

↓

Mount file system

↓

Use storage

↓

End

This flow shows how to format a storage device with a file system type like ext4 or xfs, then mount it for use.

Execution Sample

Linux CLI

sudo mkfs.ext4 /dev/sdb1
sudo mount /dev/sdb1 /mnt
ls /mnt

Formats the device /dev/sdb1 with ext4, mounts it to /mnt, then lists contents of /mnt.

Execution Table

Step	Command	Action	Output/Result
1	sudo mkfs.ext4 /dev/sdb1	Format /dev/sdb1 with ext4 file system	Filesystem created successfully
2	sudo mount /dev/sdb1 /mnt	Mount /dev/sdb1 to /mnt directory	No output (success)
3	ls /mnt	List contents of mounted device	(empty or existing files if any)
4	exit	End of process	Process complete

💡 All commands executed successfully; device formatted and mounted.

Variable Tracker

Variable	Start	After Step 1	After Step 2	After Step 3	Final
/dev/sdb1	unformatted	formatted with ext4	mounted at /mnt	accessible at /mnt	ready for use

Key Moments - 3 Insights

Why do we need to format the device before mounting?

Formatting creates a file system structure on the device (see Step 1 in execution_table). Without it, the system cannot organize files.

What happens if we try to mount without formatting?

Mounting an unformatted device will fail or show errors because no file system exists (refer to Step 2).

Why does 'ls /mnt' sometimes show empty?

After formatting and mounting a new device, it is usually empty unless files were added (Step 3).

Visual Quiz - 3 Questions

Look at the execution table, what is the state of /dev/sdb1 after Step 1?

A Formatted with ext4 file system

B Mounted at /mnt

C Unformatted

D Contains files

💡 Hint

Check the 'Action' and 'Output/Result' columns in Step 1.

At which step is the device mounted to the directory?

A Step 1

B Step 3

C Step 2

D Step 4

💡 Hint

Look for the 'mount' command in the execution_table.

If we skip formatting and run only 'mount /dev/sdb1 /mnt', what likely happens?

A Mount succeeds with no issues

B Mount fails or shows error

C Device gets formatted automatically

D Files appear in /mnt

💡 Hint

Refer to key_moments about mounting without formatting.

Concept Snapshot

File system types like ext4 and xfs organize data on storage devices.
Use 'mkfs.ext4 /dev/device' or 'mkfs.xfs /dev/device' to format.
Mount with 'mount /dev/device /mountpoint' to access files.
Formatting is required before mounting.
Listing mountpoint shows stored files or empty if new.

Full Transcript

This lesson shows how to prepare a storage device by formatting it with a file system type such as ext4 or xfs. First, you choose the device to format. Then you run a command like 'mkfs.ext4' to create the file system structure. After formatting, you mount the device to a directory so the system can access it. Finally, you can list the contents of the mounted directory to see files or confirm it is empty. Formatting is necessary before mounting; otherwise, mounting will fail. This process helps organize data on disks for Linux systems.