OPNsense Firewall & Router
Routing, Firewalling, and Network Services in Production.
Planned
OPNsense turns a plain server into a firewall and router, built on FreeBSD and the pf packet filter. This book will cover it as a production system: how interfaces and zones are defined, how stateful rules and NAT decide what passes, how WireGuard and IPsec connect sites, and how DHCP, DNS, and shaping round out the edge.
Status: planned title. Writing has not started. The repository and the cover exist; the scope below is the plan.
The first edition will ship DRM-free as PDF and EPUB, with free updates.
From interfaces to operations.
No chapters are written yet. This is the plan: the areas the book will cover, from interfaces and rules out to day-to-day operation. It targets current OPNsense releases.
- Interfaces and zones WAN, LAN, and VLANs, and how OPNsense groups and trusts them.
- Firewall rules Stateful inspection, rule order, aliases, and a default-deny posture.
- NAT Port forwards, outbound NAT, and reflection for services behind the firewall.
- VPNs WireGuard, IPsec, and OpenVPN for site-to-site and remote access.
- Network services DHCP, DNS resolution, and traffic shaping.
- Operations High availability, backups, updates, and reading the logs.
For people who own the edge of the network.
This book is for engineers who run or plan an OPNsense firewall. It assumes basic networking and explains how the pieces fit, so rules and routes stay something you can reason about.
- Network and platform engineers standing up a firewall or router and choosing OPNsense for the job.
- Operators who run the edge and want rules, NAT, and VPNs they can reason about and audit.
- Teams replacing consumer gear or a legacy firewall who need DHCP, DNS, and shaping in one place.
Planned.
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