Book Image

OPNsense Beginner to Professional

By : Julio Cesar Bueno de Camargo
5 (1)
Book Image

OPNsense Beginner to Professional

5 (1)
By: Julio Cesar Bueno de Camargo

Overview of this book

OPNsense is one of the most powerful open source firewalls and routing platforms available. With OPNsense, you can now protect networks using features that were only previously available to closed source commercial firewalls. This book is a practical guide to building a comprehensive network defense strategy using OPNsense. You’ll start with the basics, understanding how to install, configure, and protect network resources using native features and additional OPNsense plugins. Next, you’ll explore real-world examples to gain in-depth knowledge of firewalls and network defense. You’ll then focus on boosting your network defense, preventing cyber threats, and improving your knowledge of firewalling using this open source security platform. By the end of this OPNsense book, you’ll be able to install, configure, and manage the OPNsense firewall by making the most of its features.
Table of Contents (25 chapters)
1
Section 1: Initial Configuration
6
Section 2: Securing the Network
13
Section 3: Going beyond the Firewall

Basic network configuration

Local network configuration begins with a good IP addressing plan! Always try to follow the RFC1918 reserved address space (10.0.0.0/8, 172.16.0.0/12, and 192.168.0.0/16) for local networks, using private IP addresses. In this way, you avoid future issues with local addresses overlapping with public addresses on the internet. I have seen many times network administrators not paying attention to this rule of thumb and creating problems for themselves.

Another good practice is not using huge broadcast domains. If you are projecting a small network, then why use a 10.0.0.0/8 network? Avoid doing that! This can save you time in the future; for example, while connecting two or more networks using a VPN tunnel, there will be a smaller chance of network addresses overlapping with other connected networks. If you choose 10.10.10.0/24, which means 254 usable IP addresses, instead of choosing 10.0.0.0/8, which has more than 16 million IP addresses, which one do...