You're reading from OPNsense Beginner to Professional Protect networks and build next-generation firewalls easily with OPNsense

Product type Paperback

Published in Jun 2022

Publisher Packt

ISBN-13 9781801816878

Length 464 pages

Edition 1st Edition

Tools

FreeBSD

Concepts

Network Security

Author (1):

Julio Cesar Bueno de Camargo

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Table of Contents (25) Chapters

Preface

1. Section 1: Initial Configuration

2. Chapter 1: An OPNsense Overview FREE CHAPTER

3. Chapter 2: Installing OPNsense

4. Chapter 3: Configuring an OPNsense Network

5. Chapter 4: System Configuration

6. Section 2: Securing the Network

7. Chapter 5: Firewall

8. Chapter 6: Network Address Translation (NAT)

9. Chapter 7: Traffic Shaping

10. Chapter 8: Virtual Private Networking

11. Chapter 9: Multi-WAN – Failover and Load Balancing

12. Chapter 10: Reporting

13. Section 3: Going beyond the Firewall

14. Chapter 11: Deploying DHCP in OPNsense

15. Chapter 12: DNS Services

16. Chapter 13: Web Proxy

17. Chapter 14: Captive Portal

18. Chapter 15: Network Intrusion (Detection and Prevention) Systems

19. Chapter 16: Next-Generation Firewall with Zenarmor

20. Chapter 17: Firewall High Availability

21. Chapter 18: Website Protection with OPNsense

22. Chapter 19: Command-Line Interface

23. Chapter 20: API – Application Programming Interface

24. Other Books You May Enjoy

DHCP concepts

Let's suppose you are in charge of setting up a new small local network with 30 hosts, and let's assume IP version 4 (IPv4) addressing in this example. Now, think how much time setting up the IP address in each host will take. A lot, right? Setting it up in a server or gateway on the network will save a lot of time managing its IP address. So, to solve this problem, we can count on DHCP. OPNsense has a DHCP server that can be configured to deploy IP addresses to the network's hosts. DHCP works in a client/server manner, and it uses the User Datagram Protocol (UDP) to work, specifically on port 67. We will explore both IPv4 and IPv6 in this chapter. The process of a host taking a DHCP lease, which is how the IP addressing lease is named, is represented in the following diagram:

Figure 11.1 – DHCP addressing process

Next, we'll see how to configure the DHCP service on OPNsense for IPv4 addressing.