Turn Your Raspberry Pi into a Secure FTP Server with Email Relay

Got a Raspberry Pi collecting dust? Whether it's the latest Pi 5, a Pi 4, Pi Zero, or even an older model, this guide will show you how to turn it into a powerful, automated file server with email relay capabilities. Perfect for security cameras, IoT devices, and more.

Compatible with: Raspberry Pi 5, Raspberry Pi 4 Model B, Raspberry Pi 3 Model B+, Raspberry Pi 3 Model B, Raspberry Pi 2 Model B, Raspberry Pi Zero 2 W, Raspberry Pi Zero W, and Raspberry Pi Zero.

Note

This guide was tested and verified on a Raspberry Pi 3 Model B running Ubuntu Server 22.04 LTS.

What We're Building

This guide will walk you through setting up a complete system that includes:

Ubuntu Server 22.04 LTS: A rock-solid, lightweight OS for the Pi.
A Secure FTP Server (vsftpd): For dropping off files securely.
A Firewall (UFW) & Fail2ban: To keep the bad guys out.
An Automated File Processor: A script that grabs new files, emails them as attachments, and then cleans up after itself.
Email Options for Legacy Devices: Two approaches for devices that don't support modern TLS:
- Use Forward Email's legacy TLS 1.0 ports (easiest)
- Set up a Postfix SMTP relay (works with any email provider)

Ready? Let's dive in.

Part 1: Getting Ubuntu Server on Your Pi

First things first, get Ubuntu Server running on the Raspberry Pi. This is surprisingly easy thanks to the Raspberry Pi Imager.

What You'll Need

Any compatible Raspberry Pi (see list above)
A microSD card (8GB minimum, 16GB+ recommended)
A computer with a microSD card reader
Appropriate power supply for your Pi model
Internet access (Ethernet or Wi-Fi)

Note

Older models like the Raspberry Pi 2 or Pi Zero may be slower but will work fine for this setup.

Flashing the OS

Get the Raspberry Pi Imager: Download it from the official website.
Choose the OS: In the imager, select "CHOOSE OS" > "Other general-purpose OS" > "Ubuntu".
- For 64-bit models (Pi 3, 4, 5, Zero 2 W), choose "Ubuntu Server 22.04.1 LTS (64-bit)".
- For older 32-bit models (Pi 2, Pi Zero, Pi Zero W), choose "Ubuntu Server 22.04.1 LTS (32-bit)".
Pick Your Storage: Select your microSD card.

Warning

This will wipe your microSD card clean. Make sure you've backed up anything important.

Advanced Options are Your Friend: Click the gear icon (⚙️) to set up the Pi for headless mode (no monitor or keyboard needed).
- Hostname: Give your Pi a name (e.g., pi-server).
- SSH: Enable it and set a username and password.
- Wi-Fi: If you're not using Ethernet, enter your Wi-Fi details.
- Locale: Set your timezone and keyboard layout.
Write! Click the "WRITE" button and let the imager do its thing.

Booting Up & Connecting

Once the imager is done, pop the microSD card into the Pi and plug it in. Give it a few minutes to boot up. It's doing some initial setup in the background. Find its IP address from your router's admin page, then connect via SSH:

ssh your_username@your_pi_ip_address

You're in! The Raspberry Pi is now ready for configuration.

Part 2: Setting Up a Secure FTP Server

Next, set up vsftpd (Very Secure FTP Daemon), configured for maximum security.

Installation & Configuration

Install vsftpd:

sudo apt update
sudo apt install vsftpd -y

Backup the config file:

sudo cp /etc/vsftpd.conf /etc/vsftpd.conf.backup

Edit the configuration:
```
sudo nano /etc/vsftpd.conf
```

Tip

If a line is commented out (starts with a #), uncomment it by removing the #.

Make these changes:

Setting	Цінність	Purpose
`anonymous_enable`	`NO`	Disable anonymous FTP access
`local_enable`	`YES`	Allow local users to log in
`write_enable`	`YES`	Enable file uploads
`local_umask`	`022`	Set file permissions (644 for files, 755 for directories)
`chroot_local_user`	`YES`	Jail users to their home directory
`allow_writeable_chroot`	`YES`	Allow uploads in chroot jail

Add Passive Port Range: Add these lines to the end of the file. This is needed for the firewall.
```
pasv_enable=YES
pasv_min_port=40000
pasv_max_port=50000
```

Enable Logging: Add these lines to enable logging for Fail2ban.

xferlog_enable=YES
xferlog_file=/var/log/vsftpd.log
log_ftp_protocol=YES

Save and Restart: Press Ctrl+O, Enter, Ctrl+X, then restart the service:
```
sudo systemctl restart vsftpd
```

Creating an FTP User

Create a dedicated, restricted user for FTP access.

Create the user:
```
sudo adduser ftpuser
```

Follow the prompts to set a password. The other fields (name, phone, etc.) can be left blank.

Create the directory structure:

sudo mkdir -p /home/ftpuser/ftp/uploads

/home/ftpuser/ftp - Main FTP directory
- /home/ftpuser/ftp/uploads - Where files will be uploaded

Set permissions:

sudo chown -R ftpuser:ftpuser /home/ftpuser/ftp
sudo chmod 755 /home/ftpuser/ftp
sudo chmod 755 /home/ftpuser/ftp/uploads

Part 3: Firewall and Brute-Force Protection

Secure the Pi with UFW (Uncomplicated Firewall) and Fail2ban.

Setting Up UFW

Install UFW:
```
sudo apt install ufw -y
```

Set default policies:

sudo ufw default deny incoming
sudo ufw default allow outgoing

Allow SSH (critical!):

sudo ufw allow ssh comment 'SSH access'

Warning

Always allow SSH before enabling the firewall, or you'll lock yourself out!

Allow FTP ports:

sudo ufw allow 20/tcp comment 'FTP data'
sudo ufw allow 21/tcp comment 'FTP control'
sudo ufw allow 40000:50000/tcp comment 'FTP passive mode'

Enable the firewall:
```
sudo ufw enable
```

Setting Up Fail2ban

Fail2ban automatically blocks IP addresses after repeated failed login attempts.

Install Fail2ban:
```
sudo apt install fail2ban -y
```
Create a local configuration:
```
sudo nano /etc/fail2ban/jail.local
```

Add these configurations:

[DEFAULT]
bantime = 3600
findtime = 600
maxretry = 5

[sshd]
enabled = true
port = ssh
logpath = /var/log/auth.log

[vsftpd]
enabled = true
port = ftp,ftp-data,40000:50000
logpath = /var/log/vsftpd.log
maxretry = 3

Restart Fail2ban:
```
sudo systemctl restart fail2ban
```

Part 4: Automated File Processing with Email Notifications

Now for the magic: a script that monitors the FTP folder, emails new files as attachments, and deletes them. There are two approaches depending on your email provider:

Option 1: Using Forward Email API (Recommended)

If you have a Forward Email account, use the Email API for the most reliable delivery.

Get Your API Key

Log in to Forward Email
Navigate to My Account → Security
Scroll down to the "Developer Access" section at the bottom
Copy your API key

Warning

Keep your API key private at all times. Never share it publicly or commit it to version control.

Note

The Enhanced Protection plan ($3/month) or higher is required for API access.

Install inotify-tools

sudo apt install inotify-tools -y

Create the Monitoring Script

sudo nano /usr/local/bin/ftp-monitor.sh

Paste this script:

#!/bin/bash

# Configuration
WATCH_DIR="/home/ftpuser/ftp/uploads"
FROM_EMAIL="noreply@yourdomain.com"
TO_EMAIL="your-email@example.com"
API_KEY="your_forward_email_api_key"  # Replace with your actual API key

# Monitor for new files
inotifywait -m -e close_write --format '%w%f' "$WATCH_DIR" | while read FILEPATH
do
    FILENAME=$(basename "$FILEPATH")
    FOLDERNAME=$(basename "$WATCH_DIR")
    TIMESTAMP=$(date '+%Y-%m-%d %H:%M:%S')
    SUBJECT="$TIMESTAMP - $FOLDERNAME - $FILENAME"

    # Base64 encode the file
    FILE_CONTENT=$(base64 -w 0 "$FILEPATH")

    # Send email with attachment via Forward Email API
    RESPONSE=$(curl -X POST https://api.forwardemail.net/v1/emails \
      -u "$API_KEY:" \
      -H "Content-Type: application/json" \
      -d '{
        "from": "'"$FROM_EMAIL"'",
        "to": "'"$TO_EMAIL"'",
        "subject": "'"$SUBJECT"'",
        "text": "New file uploaded: '"$FILENAME"'",
        "attachments": [
          {
            "filename": "'"$FILENAME"'",
            "content": "'"$FILE_CONTENT"'",
            "encoding": "base64"
          }
        ]
      }')

    # Check if email was sent successfully
    if echo "$RESPONSE" | grep -q '"statusCode":200'; then
        echo "Email sent successfully for $FILENAME"
        # Delete the file
        rm -f "$FILEPATH"
        echo "Deleted $FILENAME"
    else
        echo "Failed to send email for $FILENAME"
        echo "Response: $RESPONSE"
    fi
done

Make it executable:

sudo chmod +x /usr/local/bin/ftp-monitor.sh

Option 2: Using Other Email Providers

If you prefer to use Gmail, Outlook, Yahoo, or another provider, modify the script to use sendmail or msmtp instead of the Forward Email API.

Install msmtp

sudo apt install msmtp msmtp-mta -y

Configure msmtp

Create the configuration file:

sudo nano /etc/msmtprc

Add your provider's settings (example for Gmail):

defaults
auth           on
tls            on
tls_trust_file /etc/ssl/certs/ca-certificates.crt
logfile        /var/log/msmtp.log

account        gmail
host           smtp.gmail.com
port           587
from           your-email@gmail.com
user           your-email@gmail.com
password       your-app-password

account default : gmail

Secure the file:

sudo chmod 600 /etc/msmtprc

Create the Alternative Monitoring Script

sudo nano /usr/local/bin/ftp-monitor.sh

Paste this script:

#!/bin/bash

# Configuration
WATCH_DIR="/home/ftpuser/ftp/uploads"
FROM_EMAIL="your-email@gmail.com"
TO_EMAIL="recipient@example.com"

# Monitor for new files
inotifywait -m -e close_write --format '%w%f' "$WATCH_DIR" | while read FILEPATH
do
    FILENAME=$(basename "$FILEPATH")
    FOLDERNAME=$(basename "$WATCH_DIR")
    TIMESTAMP=$(date '+%Y-%m-%d %H:%M:%S')
    SUBJECT="$TIMESTAMP - $FOLDERNAME - $FILENAME"

    # Send email with attachment using msmtp
    (
        echo "To: $TO_EMAIL"
        echo "From: $FROM_EMAIL"
        echo "Subject: $SUBJECT"
        echo "MIME-Version: 1.0"
        echo "Content-Type: multipart/mixed; boundary=\"BOUNDARY\""
        echo ""
        echo "--BOUNDARY"
        echo "Content-Type: text/plain; charset=utf-8"
        echo ""
        echo "New file uploaded: $FILENAME"
        echo ""
        echo "--BOUNDARY"
        echo "Content-Type: application/octet-stream; name=\"$FILENAME\""
        echo "Content-Transfer-Encoding: base64"
        echo "Content-Disposition: attachment; filename=\"$FILENAME\""
        echo ""
        base64 "$FILEPATH"
        echo ""
        echo "--BOUNDARY--"
    ) | msmtp -t

    # Check if email was sent successfully
    if [ $? -eq 0 ]; then
        echo "Email sent successfully for $FILENAME"
        # Delete the file
        rm -f "$FILEPATH"
        echo "Deleted $FILENAME"
    else
        echo "Failed to send email for $FILENAME"
    fi
done

Make it executable:

sudo chmod +x /usr/local/bin/ftp-monitor.sh

Create a Systemd Service

sudo nano /etc/systemd/system/ftp-monitor.service

Add this content:

[Unit]
Description=FTP Upload Monitor
After=network.target

[Service]
Type=simple
ExecStart=/usr/local/bin/ftp-monitor.sh
Restart=always
RestartSec=10

[Install]
WantedBy=multi-user.target

Enable and start the service:

sudo systemctl daemon-reload
sudo systemctl enable ftp-monitor.service
sudo systemctl start ftp-monitor.service

Check the status:

sudo systemctl status ftp-monitor.service

Part 5: Email Options for Legacy Devices

Devices like FOSSCAM cameras often don't support modern TLS versions. There are two solutions:

Option 1: Use Forward Email's Legacy TLS 1.0 Ports (Recommended)

If you're using Forward Email, this is the easiest solution. Forward Email provides dedicated legacy TLS 1.0 ports specifically for older devices like cameras, printers, scanners, and fax machines.

Pricing

Forward Email offers several plans:

Plan	Price	Features
Free	$0/month	Email forwarding only (no sending)
Enhanced Protection	$3/month	SMTP access + legacy TLS 1.0 ports
Team	$9/month	Enhanced + team features
Enterprise	$250/month	Team + unlimited API requests

Important

The Enhanced Protection plan ($3/month) or higher is required for SMTP access and legacy TLS 1.0 port support.

Learn more at Forward Email Pricing.

Generate Your Password

Before configuring your device, generate a password in Forward Email:

Log in to Forward Email
Navigate to My Account → Domains → [Your Domain] → Aliases
Create or select an alias (e.g., camera@yourdomain.com)
Click "Generate Password" next to the alias
Copy the generated password - you'll use this for SMTP authentication

Tip

Each alias can have its own password. This is useful for tracking which device sent which email.

Configure Your Device

Use these settings in your camera, printer, scanner, or other legacy device:

Setting	Цінність
SMTP Server	`smtp.forwardemail.net`
Port (SSL/TLS)	`2455`
Port (STARTTLS)	`2555`
Ім'я користувача	Your alias email (e.g., `camera@yourdomain.com`)
Пароль	The password from "Generate Password"
Authentication	Необхідно
Encryption	SSL/TLS or STARTTLS

Warning

These ports use the deprecated TLS 1.0 protocol which has known security vulnerabilities (BEAST, POODLE). Use only if your device cannot support modern TLS 1.2+.

Simply configure your device with these settings and it will send emails directly through Forward Email without needing a local relay server.

For more details, see the Forward Email FAQ on Legacy TLS Support.

Option 2: Set Up a Postfix SMTP Relay

If you're not using Forward Email, or prefer a local relay solution, set up Postfix on the Raspberry Pi to act as a middleman. This works with any email provider (Gmail, Outlook, Yahoo, AOL, etc.).

Install Postfix

sudo apt update
sudo apt install postfix mailutils libsasl2-modules -y

During installation:

Select "Internet Site"
Enter your Pi's hostname (e.g., raspberrypi-ftp) for "System mail name"

Choose Your Email Provider

Провайдер	SMTP Server	Port	App Password Required?
Gmail	smtp.gmail.com	587	Yes
Перспектива	smtp-mail.outlook.com	587	Yes
Yahoo	smtp.mail.yahoo.com	465	Yes
AOL	smtp.aol.com	587	Yes

Get an App-Specific Password

Most providers require app passwords for third-party applications. Generate one from your email provider's security settings:

Important

Never use your regular email password. Always use an app-specific password.

Configure SASL Authentication

Create the password file for your chosen provider. This example uses Yahoo:

sudo mkdir -p /etc/postfix/sasl
sudo chmod 700 /etc/postfix/sasl
sudo nano /etc/postfix/sasl/sasl_passwd

Add this line (adjust server and port for your provider):

[smtp.mail.yahoo.com]:465 your_email@yahoo.com:your_app_password

For Gmail, use:

[smtp.gmail.com]:587 your_email@gmail.com:your_app_password

Secure and hash the file:

sudo chmod 600 /etc/postfix/sasl/sasl_passwd
sudo postmap /etc/postfix/sasl/sasl_passwd

Configure Email Address Mapping

Rewrite local email addresses to match your email provider:

sudo mkdir -p /etc/postfix/map
sudo chmod 700 /etc/postfix/map
sudo nano /etc/postfix/map/regex_map

Add this line (replace HOSTNAME with your Pi's hostname and use your email):

/.+@HOSTNAME/    your_email@provider.com

Example:

/.+@raspberrypi-ftp/    john@yahoo.com

Secure the file:

sudo chmod 600 /etc/postfix/map/regex_map

Configure Postfix Main Settings

Edit the main configuration:

sudo nano /etc/postfix/main.cf

Find and update the relay host (or add at the end):

relayhost = [smtp.mail.yahoo.com]:465

Add these settings at the end of the file:

# SMTP Relay Configuration
smtp_use_tls = yes
smtp_sasl_auth_enable = yes
smtp_sasl_security_options = noanonymous
smtp_sasl_password_maps = hash:/etc/postfix/sasl/sasl_passwd
smtp_tls_CAfile = /etc/ssl/certs/ca-certificates.crt
smtp_tls_wrappermode = yes
smtp_tls_security_level = encrypt
smtp_generic_maps = regexp:/etc/postfix/map/regex_map

# Network settings
inet_interfaces = all
inet_protocols = ipv4
mynetworks = 127.0.0.0/8 [::1]/128 192.168.1.0/24

Tip

For Gmail (port 587), set smtp_tls_wrappermode = no instead of yes.

Warning

Update mynetworks with your actual network range. Only add trusted networks - any device on these networks can relay mail without authentication.

Common network ranges:

Network Range	IP Address Range
`192.168.0.0/24`	192.168.0.1 - 192.168.0.254
`192.168.1.0/24`	192.168.1.1 - 192.168.1.254
`10.0.0.0/8`	10.0.0.0 - 10.255.255.255

Update Firewall and Restart

sudo ufw allow 25/tcp comment 'SMTP for local devices'
sudo systemctl restart postfix

Verify Postfix is running:

sudo systemctl status postfix

Test the Relay

Send a test email:

echo "Test from Postfix" | mail -s "Test" your_email@provider.com

Check the logs:

sudo tail -f /var/log/mail.log

Look for status=sent to confirm success.

Configure Your Device

In your camera or device settings:

SMTP Server: Your Pi's IP address (e.g., 192.168.1.100)
SMTP Port: 25
Authentication: None
Encryption: None (local network only)

Troubleshooting

If issues arise, check these log files:

FTP Server:

sudo tail -f /var/log/vsftpd.log

Fail2ban:

sudo fail2ban-client status
sudo tail -f /var/log/fail2ban.log

File Monitor:

sudo journalctl -u ftp-monitor.service -f

Postfix Mail:

sudo tail -f /var/log/mail.log
mailq  # View mail queue

Wrapping Up

The Raspberry Pi is now a complete automated system with secure file uploads, automatic email notifications with attachments, and SMTP relay capabilities for legacy devices. Whether using Forward Email's legacy TLS ports or a local Postfix relay, older devices can now send emails reliably through modern email providers.