🔐 Raspberry Pi – User Management & Permissions (2025 Beginner Guide)

---

🧲 Introduction – Why User Management Matters on Raspberry Pi?

Linux-based systems like Raspberry Pi OS treat users, groups, and permissions as the backbone of system security. Whether you’re running a single Pi or managing multiple devices, understanding how to create users, assign roles, and set permissions ensures secure and smooth operation.

🎯 In this guide, you’ll learn:

• How to create, delete, and manage users and groups
• How Linux file and directory permissions work
• Using sudo, chmod, chown, and groups
• Best practices for secure and organized user management

---

👤 Raspberry Pi Default User Info

By default, Raspberry Pi OS uses:

🔑 Username	📦 Description
pi	Default user with sudo privileges
root	Disabled by default for safety

🔐 As of newer Raspberry Pi OS releases, you are prompted to create a new user on first boot for improved security.

---

➕ How to Add a New User

To create a new user with a home directory:

sudo adduser <username>

🔍 Example:

sudo adduser alex

📌 Follow the prompts to set a password and full name (optional).

---

👥 Add User to Sudo Group

To give the new user admin rights:

sudo usermod -aG sudo <username>

Example:

sudo usermod -aG sudo alex

✅ You can now run sudo commands as that user.

---

❌ Delete a User Safely

To delete a user but keep their files:

sudo deluser <username>

To delete a user and their home directory:

sudo deluser --remove-home <username>

🧼 This is useful when decommissioning users on shared Raspberry Pi setups.

---

👪 Create and Manage Groups

Groups allow permission control over files and devices.

🧪 Command	📘 Description
sudo addgroup <groupname>	Create a new group
sudo usermod -aG group user	Add a user to a group
groups <username>	List user’s group memberships

🔍 Example:

sudo addgroup developers
sudo usermod -aG developers alex

---

🔐 Understanding File Permissions

Each file and folder has three levels of permissions: Owner, Group, Others

ls -l

Example output:

-rw-r--r-- 1 pi pi  1024 Jan 1 10:00 notes.txt

Part	Meaning
-rw-r--r--	Permissions: read/write owner, read-only for group/others
1	Number of hard links
pi	Owner name
pi	Group name

---

✏️ Change File Permissions with chmod

🧪 Command	📘 Use Case
chmod +x <file>	Make script executable
chmod 644 <file>	Owner read/write, others read
chmod 755 <file>	Executable by all, writable by owner

Example:

chmod 700 secret.sh

---

🔄 Change Ownership with chown

To change file owner:

sudo chown alex:alex notes.txt

To give ownership recursively:

sudo chown -R alex:alex /home/alex

✅ Useful when transferring project files between users.

---

📜 Sudo: Run as Root Privileges

The sudo command allows users in the sudo group to execute commands with administrative privileges:

sudo apt update

To switch to root shell (temporarily):

sudo -i

---

📦 System-Wide User Info Files

📁 File	📘 Description
/etc/passwd	Contains user account info
/etc/shadow	Stores encrypted passwords
/etc/group	Group definitions and user associations
/etc/sudoers	Defines who can run what with sudo

⚠️ Always use visudo to safely edit /etc/sudoers.

---

🧠 Best Practices for User Management

• 🔒 Avoid logging in as root — use sudo instead
• 🧑‍🤝‍🧑 Create a unique user for each person using the Pi
• 🔐 Use strong passwords or SSH key authentication
• 🔁 Review group permissions regularly for security
• 📁 Limit writable directories for non-admin users

---

📌 Summary – Recap & Next Steps

User and permission management in Linux is key to keeping your Raspberry Pi secure and organized—especially when multiple users or sensitive files are involved.

🔍 Key takeaways:

• Use adduser, deluser, and usermod to manage users and roles
• File permissions define access for owner, group, and others
• chmod, chown, and groups are vital tools for permission control
• Always manage sudo rights cautiously

⚙️ Real-world relevance: Perfect for projects requiring team access, IoT device security, or hosting public-facing services on your Raspberry Pi.

---

❓ FAQs – Raspberry Pi User Management

❓ How do I enable root user on Raspberry Pi?

✅ You can set a root password:

sudo passwd root

Then log in with su -. Not recommended for daily use.

---

❓ How can I give a user sudo access?

✅ Add them to the sudo group:

sudo usermod -aG sudo username

---

❓ How do I view all users on Raspberry Pi?

✅ Use:

cut -d: -f1 /etc/passwd

---

❓ How can I list all groups a user belongs to?

✅ Use:

groups <username>

---

❓ What’s the safest way to edit sudo privileges?

✅ Use:

sudo visudo

This checks syntax before saving to prevent system lockout.

---

Share Now :