Implement and Configure Firewalls on Linux Systems (XK0-006)

This lab aligns to the following CompTIA Linux+ (XK0-006) exam objectives: 

  • 3.2: Given a scenario, configure and implement firewalls on a Linux system.
  • 5.3: Given a scenario, analyze and troubleshoot networking issues on a Linux system.
  • 5.4: Given a scenario, analyze and troubleshoot security issues on a Linux system.

By the end of this lab, you will be able to:

  • Configure and manage firewall rules using firewalld, iptables, ufw, and nftables on a Linux system.
  • Apply stateful and stateless firewall filtering to control inbound and outbound network traffic.
  • Implement source-based access control using ipset.
  • Configure Network Address Translation (NAT) and IP forwarding on a Linux server. 

Overview

Welcome to the Implement and Configure Firewalls on Linux Systems lab. In this lab, you will configure and test multiple firewall technologies on an AlmaLinux system while using an Ubuntu device to verify connectivity and access control. Building on core networking concepts, you will examine how traffic flows between systems and how firewall rules influence that communication.

You will work with firewalld, nftables, iptables, ufw, and ipset as you enforce traffic rules, test service access, and control inbound connections. As you progress, you will validate connectivity, observe how traffic is allowed or denied, and ensure that firewall behavior aligns with expected network communication.

You will also configure NAT masquerading and enable IP forwarding to support routed network scenarios. By the end of this lab, you will be able to configure, verify, and explain Linux firewall behavior across multiple tools while understanding how firewall rules interact with underlying network configuration.

You will complete the following two activities in this lab:

  • Reading Assignment – Networking and Troubleshooting
  • Exercise 1 –  Implement and Configure a Linux Firewall

Click Next to continue.

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