Chmod Recursive Guide: How To Change Permissions In Linux

Have you ever faced being stuck solving file permissions in Linux? You are not on your own. Knowledge of chmod recursive can save your hours of frustration. Whether setting up your first web server or organizing project files, you should know how to set permissions in the right way.

The guide is directed toward students who may be testing their projects at school and young professionals who may be working in production. Let’s finally get the Linux file permission straight.

Table of Contents

Why Permissions Matter

Before diving into chmod -R, it’s important to understand why Linux permissions are critical.

Linux is a multi-user system. Proper permissions:

Protect sensitive data
Prevent accidental changes
Control who can access or modify your files

Without proper permission management, you risk:

Data leaks
System crashes
Security vulnerabilities

That’s where chmod -R (chmod recursive) steps in!

1. What is chmod?

The chmod Command changes file and directory permissions.

It controls three actions:

Read (r) — View file contents or list a directory
Write (w) — Modify file contents or create/delete files inside a directory
Execute (x) — Run scripts/binaries or enter a directory

It applies to three categories:

User (u) – Owner
Group (g) – Group members
Others (o) – Everyone else

2. Understanding Linux Permissions: Basics You Must Know

When you run ls -l, you’ll see something like:

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drwxr-xr-x 2 user group 4096 Apr 27 10:00 myfolder

Breakdown:

d → directory
rwx → User: read, write, execute
r-x → Group: read, execute
r-x → Others: read, execute

Permissions use numbers too:

Action	Value
Read (r)	4
Write (w)	2
Execute (x)	1

Examples:

7 = read + write + execute (4+2+1)
5 = read + execute (4+1)

3. What Does Recursive Mean in chmod Recursive?

When you use the -R flag:

It recursively applies permission changes to all files, subfolders, and their contents.
Saves time when updating multiple files/folders.

Command structure:

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chmod -R [permissions] [directory-name]

Example:

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chmod -R 755 /home/username/project

This applies permission 755 to the folder and everything inside it.

4. When Should You Use chmod -R?

Use chmod recursive when:

You manage large directories with subfolders
Deployment needs permission updates
Backup directories need controlled access
Setting up shared resources (like public folders or website directories)

5. Different Ways to Set Permissions Recursively

Using Numbers

bash

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chmod -R 755 /path/to/directory

Using Symbols

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chmod -R u=rwx,g=rx,o=rx /path/to/directory

Meaning:

User: Read, Write, Execute
Group: Read, Execute
Others: Read, Execute

6. Practical Examples of chmod Recursive

Example 1: Web Server Directory

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chmod -R 755 /var/www/html

Gives users access to view and execute files on the web without the ability to modify them.

Example 2: Private Project Folder

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chmod -R 700 ~/private_project

Only you (the owner) can access it.

7. Best Practice: Set Different Permissions for Files vs Directories

Directories need execute permission to be accessed, but regular files don’t.

Here’s the best practice:

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# Directories: 755

find /your/folder -type d -exec chmod 755 {} \;

# Files: 644

find /your/folder -type f -exec chmod 644 {} \;

Why?

Directories → Need x to enter
Files → No need for x (execute)

8. Real-World Use Cases of chmod Recursive

Situation	Command
Deploying a static website	chmod -R 755 /var/www/html/
Securing private folders	chmod -R 700 /home/user/private/
Preparing a software package for release	chmod -R 755 /release-folder/

Pro Tip: Always check folder permissions after running recursive commands using ls -l.

9. Mistakes to Avoid with chmod Recursive

Using 777 everywhere: Full permission to everyone (huge security risk).
Changing system directories like /etc accidentally: Could break your system.
Not verifying results: Always double-check with ls -l.
Assuming all files need execute: Only scripts and binaries need x.

10. Bonus Tip: How to Undo chmod Recursive?

There is no direct “undo,” but you can:

Backup permissions using getfacl:

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getfacl -R /path/to/dir > permissions.bak

Restore permissions later with setfacl:

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setfacl –restore=permissions.bak

11. Why You Should Think Twice Before Running chmod -R as Root

If you’re logged in as root or using sudo and you run a recursive chmod, pause for a second.

Because when you’re root:

Linux won’t stop you from changing permissions on critical system files.

One wrong command like:
bash
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sudo chmod -R 777 /

could cripple your operating system (yes, even before you realize it).

12. How chmod -R Can Save You Hours During Deployments

Imagine you’ve just finished coding your website. You excitedly deploy it to your server… and boom:

Some images don’t load.
CSS files return 403 errors.
Scripts won’t execute.

What happened? Permissions chaos.

Here’s where chmod -R saves the day:

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chmod -R 755 /var/www/html

Now:

Directories are accessible.
Static files load correctly.
Executables run as expected.

13. chmod -R and Security: Striking the Right Balance

Here’s a small but crucial truth:
Security is a balancing act in Linux.

If you’re too strict with permissions:

Apps may fail.
Collaborators may lose access.

If you’re too lenient:

You open doors to hackers.
You risk accidental deletions.

Best Practice Approach:

For shared folders, give group write access carefully:
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chmod -R 775 /shared-folder

For private projects, lock it down:

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chmod -R 700 ~/important-stuff

Learn More with PW Skills!

Understanding and using chmod recursive effectively is a must-have Linux skill.
It makes managing files, securing data, and collaborating in projects much smoother.

Remember:

Think before you change permissions
Backup important permissions if necessary

Master chmod -R, and you’ll be far ahead in Linux administration, DevOps, and even everyday tech tasks.
Want to become an expert in Linux, Cloud Computing, and DevOps? Join the PW Skills DevOps and Cloud Computing course today!