Introduction
But as many developers and hobbyists quickly realize, setting up remote access behind firewalls or NAT routers is not always straightforward.
This article will explain various ways to remotely access Raspberry Pi and IoT devices behind firewalls and routers, compare solutions, and share security best practices to keep your devices safe.
The Problem with NAT and Firewalls
When you want to remotely access IoT devices behind a router, you need to work around these barriers while keeping security intact.
Challenges include:
Private IP addresses not accessible externally
Firewalls blocking inbound traffic
ISP restrictions on port forwarding
Security risks of exposing devices online
How to Connect Devices Behind Routers and Firewalls
1. Port Forwarding
By forwarding a specific port to your Raspberry Pi or IoT device, you can access it using your public IP.
2. Dynamic DNS (DDNS)
Since most ISPs assign dynamic IP addresses, you can use a Dynamic DNS service to keep track of your changing IP.
3. VPN (Virtual Private Network)
This way, you bypass firewall restrictions and safely access IoT devices behind a firewall.
4. Reverse SSH Tunneling
This avoids port forwarding and works even if the device is behind strict NAT.
5. Third-Party Remote Access Services
Cloud-based solutions such as Ngrok, ZeroTier, Tailscale, or Dataplicity make remote access simple.
Step-by-Step: Remotely Access Raspberry Pi Behind Firewall Using Reverse SSH
Prepare a Remote Server
You’ll need a VPS (Virtual Private Server) or cloud server with a public IP address.
Create SSH Keys
Generate SSH keys on your Raspberry Pi and copy them to the remote server for secure authentication.
Set Up Reverse Tunnel
ssh -R 2222:localhost:22 [email protected]
This command allows you to SSH into your VPS and then access your Raspberry Pi on port 2222.
Automate the Connection
This ensures your Raspberry Pi behind router remains accessible.
How VPNs Simplify Remote Connections
By creating a private encrypted network, your IoT devices and Raspberry Pi become part of the same network as your remote computer.
Options include:
Running OpenVPN or WireGuard on Raspberry Pi
Using routers with built-in VPN servers
Cloud VPNs like Tailscale or ZeroTier for simplified configuration
Cloud-Based Remote Access Tools
Ngrok
Great for testing or lightweight use.
Dataplicity
It allows web-based terminal access and easy device management.
Tailscale / ZeroTier
Perfect for managing multiple IoT devices securely.
Safe Remote Connections
Here are security best practices:
Use SSH keys instead of passwords
Enable firewalls on Raspberry Pi and IoT devices
Keep software and firmware updated
Use strong VPN encryption
Limit access with IP whitelisting
Security should never be an afterthought when setting up remote access behind firewalls or routers.
Practical Applications
Home automation: Monitor and control smart devices from anywhere
IoT projects: Remotely update and debug devices in real-world deployments
Media servers: Access your Raspberry Pi-powered media server remotely
Learning and development: Students can practice coding on Raspberry Pi remotely access Raspberry Pi behind router without physical access
Business IoT systems: Manage industrial IoT devices behind corporate firewalls securely
Trends in Remote Connectivity
Zero-trust networking, cloud-native VPNs, and AI-driven security will dominate the future.
Conclusion
Whether you’re a hobbyist working with Raspberry Pi behind a router or a developer managing IoT devices behind firewalls, having reliable and secure remote access is essential.
The key is balancing convenience with security—using trusted tools, encrypting connections, and keeping your devices protected.