HOW TO BUILD A DUAL-ISP REDUNDANT NETWORK for Reliable and Secure Internet Connectivity

Step-by-Step Dual ISP Setup, Configuration, and Security Guide

By: Practicing Engineers Network

Narrated by: Virtual Voice

How to Build a Dual-ISP Redundant Network for Reliable and Secure Internet Connectivity

Step-by-Step Dual ISP Setup, Configuration, and Security Guide
Prepared by Practicing Engineers Network

Keep your business online — even when one ISP fails.
This hands-on guide shows you exactly how to design, configure, and secure a dual-ISP redundant network to ensure continuous, reliable, and secure Internet access. Written in a clear, practical format, this book walks you through every step — from initial design and hardware setup to advanced routing, failover testing, and security hardening.

Whether you’re an IT professional, network engineer, or small business owner, you’ll gain the knowledge to build a robust and fault-tolerant Internet connection using today’s most common platforms.

What You’ll Learn

• How to connect two Internet service providers (ISPs) for automatic failover and load balancing

• Step-by-step setup for pfSense, Cisco, FortiGate, and Ubiquiti systems

• Design topologies for single-firewall, HA firewall pairs, and BGP multihoming

• Configure VLANs, NAT, VPNs, and firewall rules for security and segmentation

• Implement WAN health checks, SD-WAN, and dynamic routing (BGP/iBGP)

• Test and validate redundancy with monitoring, logging, and automation scripts

• Apply Zero Trust and security hardening principles for small business networks

• Use ready-made templates for documentation, change logs, and validation

Inside the Book

📘 Part I – Fundamentals: Understanding redundancy and connection types
⚙️ Part II – Core Design: Addressing, VLANs, and firewall architecture
🔧 Part III – Implementation: pfSense, Cisco, FortiGate, and Ubiquiti configurations
🧠 Part IV – Advanced Topics: BGP, SD-WAN, and security hardening
📊 Part V – Case Studies: Real-world office and multi-site examples
🗂️ Part VI – Appendices: Worksheets, templates, and command references

Who This Book Is For

• Network engineers, IT administrators, and consultants

• Small business owners building reliable network infrastructure

• Students preparing for real-world networking and cybersecurity roles

Why This Book Is Different

Unlike theoretical networking books, this is a true step-by-step field manual—every concept includes visual diagrams, configuration snippets, and test procedures used by practicing engineers in real-world deployments.

Ensure uptime, strengthen security, and build confidence in your network design—one step at a time.
Get your copy today and start building a resilient dual-ISP network that keeps your business connected 24/7.