Overview¶

Linux provides built-in utilities to monitor disk usage and storage consumption. The most commonly used commands are:

du → Disk usage of files and directories
df → Disk space usage of file systems

These commands are essential for:

System monitoring
Storage management
Troubleshooting disk-related issues

du — Disk Usage¶

Description¶

du (Disk Usage) estimates how much space files and directories consume.

Basic Usage¶

du

Explanation
Displays disk usage of the current directory and its subdirectories (in bytes by default).

Human Readable Summary¶

du -sh *

Explanation

-s → summarize total size per item
-h → human-readable format (KB, MB, GB)
* → applies to all files/directories in current location

Example Output¶

4.0K file1.txt
12M folder1
2.5G folder2

Show Total Usage¶

du -shc *

Explanation

-c → adds a total at the end

Example Output¶

4.0K file1.txt
12M folder1
2.5G folder2
2.6G total

Common du Options¶

Option	Description
`-s`	Summarize
`-h`	Human readable
`-c`	Show total
`-a`	Include files (not just directories)

Practical Examples¶

Check current directory size¶

du -sh .

Find large directories¶

du -h --max-depth=1

Explanation
Shows size of directories up to one level deep.

df — Disk Filesystem Usage¶

Description¶

df (Disk Free) reports available and used disk space on file systems.

Basic Usage¶

df

Explanation
Displays disk usage in blocks for all mounted file systems.

Human Readable Output¶

df -h

Explanation

Converts sizes into KB, MB, GB
Easier to interpret storage usage

Example Output¶

Filesystem      Size  Used Avail Use% Mounted on
/dev/sda1        50G   20G   28G  42% /

Filter by File System Type¶

df -ht ext4

Explanation

-t → specify file system type
Shows only selected types (e.g., ext4, ext3)

Common df Options¶

Option	Description
`-h`	Human readable
`-t`	Filter by file system
`-a`	Show all file systems

Practical Examples¶

Check root partition usage¶

df -h /

Check specific filesystem¶

df -ht ext4

Difference Between du and df¶

Feature	du	df
Purpose	File/directory size	Filesystem usage
Scope	Specific paths	Entire disk partitions
Output	File-level details	Disk-level summary

Important Notes¶

du helps find which files consume space
df helps check overall disk capacity
Use both together for effective disk management

Summary Table¶

Command	Purpose
`du`	Check file/directory usage
`du -sh *`	Summarized human-readable usage
`du -shc *`	Include total usage
`df`	Show disk filesystem usage
`df -h`	Human-readable disk usage
`df -ht ext4`	Filter by filesystem

Conclusion¶

The du and df commands are essential tools for:

Monitoring storage usage
Identifying large files/directories
Managing disk space efficiently

Understanding these commands helps maintain system performance and avoid storage-related issues.