Build a Raspberry Pi NAS in Under 50 Minutes

A quick tutorial for setting up network file sharing with read-only guest access and full access for authenticated users.

Source: Based on PCMag's Raspberry Pi NAS tutorial by Whitson Gordon

Time: ~50 minutes | Difficulty: Beginner-friendly

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What You'll Need

• Raspberry Pi (any model, Pi 4+ recommended)
• Power supply & microSD card (8GB+)
• External USB drive (wall-powered or via powered USB hub)
• Ethernet cable (optional but recommended for speed)
• Keyboard, mouse, monitor (for initial setup)

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Part 1: Initial Setup (15 min)

1. Install Raspbian OS

Use Raspberry Pi Imager to flash Raspbian to your microSD card. Boot up the Pi, create a password, and run initial updates.

Connect via Ethernet for faster file transfers. SSH works too if you prefer remote setup.

2. Update System & Install Samba

sudo apt update
sudo apt upgrade
sudo apt install samba samba-common

What this does: Updates package lists, upgrades installed packages, then installs Samba (the file-sharing software).

When prompted about WINS settings, choose Yes.

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Part 2: Prepare Your Drive (15 min)

3. Find Your Drive

sudo fdisk -l

What this does: Lists all connected disks. Identify your external drive (e.g., /dev/sda).

⚠️ Warning: The following steps will ERASE your drive. Back up any important data first.

4. Unmount the Drive

umount /dev/sda1

What this does: Disconnects the drive so you can modify it. Adjust numbers if you have multiple partitions (sda2, sda3, etc.).

5. Partition the Drive

sudo parted /dev/sda

In the Parted wizard, enter these commands one by one:

mklabel gpt
mkpart

When prompted, enter:

• Partition name: MyExternalDrive (or your choice)
• File system type: ext4
• Start: 0%
• End: 100%

Type quit to exit.

What this does: Creates a new GPT partition table and one partition using the entire drive.

6. Format the Partition

sudo mkfs.ext4 /dev/sda1
sudo e2label /dev/sda1 MyExternalDrive

What this does: Formats the partition with ext4 filesystem and labels it. This takes a few minutes for large drives.

7. Reboot and Set Permissions

sudo shutdown -r now

After reboot:

sudo chown -R pi:pi /media/pi/MyExternalDrive/
sudo chmod -R 755 /media/pi/MyExternalDrive/
sudo chmod 755 /media/pi/

What this does: Gives your user ownership of the drive and makes directories readable by guests.

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Part 3: Configure File Sharing (15 min)

8. Edit Samba Configuration

sudo nano /etc/samba/smb.conf

Scroll to the bottom and add:

[MyMedia]
path = /media/pi/MyExternalDrive/
writeable = no
read only = yes
create mask = 0555
directory mask = 0555
public = yes
guest ok = yes
guest only = yes
browseable = yes
force user = pi

[MyMedia-Write]
path = /media/pi/MyExternalDrive/
writeable = yes
read only = no
create mask = 0775
directory mask = 0775
valid users = pi
browseable = yes
guest ok = no

What this does:

• MyMedia = Read-only share for guests
• MyMedia-Write = Full access share requiring authentication
• force user = pi = Guests borrow your user's read permissions
• guest ok = yes = Allows passwordless guest access

Press Ctrl+X, then Y, then Enter to save and exit.

9. Create Samba Password

sudo smbpasswd -a pi

What this does: Sets a password for Samba access. Can be different from your Pi's login password.

Optional: Add more users with sudo adduser username then sudo smbpasswd -a username

10. Restart Samba

sudo systemctl restart smbd nmbd

What this does: Applies your configuration changes.

11. Verify Configuration

testparm -s

What this does: Checks for syntax errors in your Samba config.

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Part 4: Connect & Test (5 min)

From Windows:

1. Open File Explorer
2. Type in address bar: \\raspberrypi\MyMedia (guest access) or \\raspberrypi\MyMedia-Write (full access)

From Mac:

1. Finder → Cmd+K
2. Enter: smb://raspberrypi/MyMedia (guest) or smb://raspberrypi/MyMedia-Write (authenticated)
3. Select Guest or enter your username/password

Troubleshooting: If hostname doesn't work, use IP address instead: \\192.168.1.X\MyMedia or smb://192.168.1.X/MyMedia

Find your Pi's IP with: hostname -I

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Understanding Key Concepts

Samba: Open-source implementation of SMB/CIFS file sharing protocol (Windows-compatible)

Guest Access: Passwordless, read-only access for casual viewing

Force User: Makes guests act as your user for file permissions (but Samba still prevents writing)

Valid Users: Restricts share access to specific authenticated users

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What's Next?

• Add more drives and create separate shares
• Set up automatic backups with rsync
• Configure static IP address for easier access
• Add time machine support for Mac backups

Important: This setup isn't RAID-protected. Always backup critical data elsewhere!

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Quick Reference

# Find Pi IP address
hostname -I

# Check drive status
df -h

# View Samba logs
sudo tail -f /var/log/samba/log.smbd

# Restart Samba after changes
sudo systemctl restart smbd nmbd

# Test configuration
testparm -s