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Linux Networking & Security Fundamentals

Topic: Security
David Prowse

Fundamental knowledge of Linux server networking and securing is vital for systems administrators, developers, and many other types of computer technicians. In some cases, these important basics are either underestimated, or are not properly incorporated into Linux environments. By implementing strong networking and security techniques, Linux systems can communicate more efficiently and safely, resulting in increased production, reduced downtime, and happier organizations.

What you'll learn-and how you can apply it

  • Learn how Linux servers and the various Linux networking services operate, and how to configure them.
  • Use networking utilities to test Linux systems and verify that they are functioning properly.
  • Learn about firewalls and user security.
  • Utilize tools such as SSH securely and effectively.

This training course is for you because...

  • You want to learn the fundamentals of Linux networking and Linux security.
  • You are an aspiring Linux administrator/systems administrator.
  • You wish to increase your overall knowledge of the Linux operating system.


Course Set-up

  • A virtualization platform of your choice. For example, VirtualBox: https://www.virtualbox.org/wiki/Downloads, or VMware Workstation, KVM, and so on. It is recommended that you utilize NAT mode and not bridged mode. If using VirtualBox, create and select “NAT Network” for your virtual machines’ networking connectivity.
  • At a minimum, download and install the following Linux operating systems into virtual machines: Debian (as a server, no desktop environment): https://www.debian.org/distrib/; and at least one Linux client with desktop environment (Debian, Ubuntu Desktop, Fedora Workstation, etc.) These operating systems will need to be able to communicate with each other and connect to the Internet.
  • Go to https://prowse.tech/webinars for details on how to setup your virtual environment and Linux systems.

Recommended Preparation

Recommended Follow-up

About your instructor

  • Dave Prowse is an author, technologist, and technical trainer. As a consultant, he supports a variety of servers, virtualization platforms, and software. He has written two dozen books for Pearson Education, including the well-received CompTIA A+ Exam Cram and CompTIA Security+ Cert Guide. He also develops video content, including the CompTIA A+ LiveLessons video course. He has taught many computer courses in Linux and CompTIA certifications, both in the classroom and on the Internet. David has 20 years of experience in the IT field, and loves to share that experience with his readers, watchers, and students. He runs the website dprocomputer.com in support of his books, videos, and webinars.


The timeframes are only estimates and may vary according to how the class is progressing

Day 1: Linux Networking Fundamentals

Introduction (5 min)

  • Course introduction
  • Overview of two-day agenda

Segment 1: Networking 101 (20 min)

  • What is a computer network?
  • How do computers communicate over the network? And why?
  • Introduction to Linux tools used for network analysis.

Segment 2: Linux Networking Services and Configuration Files (70 min)

  • networking.service
  • systemd-networkd
  • NetworkManager
  • Netplan
  • Quiz

10 minute break

Segment 3: Networking Commands and Configurations (70 min)

  • ping
  • hostnames and resolution
  • ip
  • nmcli
  • netstat, lsof and ss
  • Quiz

10 minute break

Segment 4: Connecting Between Hosts with the Command Line (40 min)

  • SCP
  • SSH

Segment 5: Wrap-up for the Day (15 min)

  • Q&A
  • Additional coverage of topics based on questions (time allowing)

Day 2: Linux Security Fundamentals

Introduction (5 min)

  • Overview of day two agenda

Segment 1: Security 101 (20 min)

  • Nothing is 100% Secure!
  • The CIA Triad
  • Security Catch Phrases
  • Quiz

Segment 2: Working with Services (25 min)

  • Displaying Services and their Status
  • Starting/Stopping, Enabling/Disabling Services
  • Reducing the Attack Surface... with less Services!

Segment 3: Updates & Upgrades (15 min)

  • apt update
  • dnf update

10 minute break

Segment 4: Firewalls (50 min)

  • Types of Firewalls
  • iptables/nwtables
  • firewalld
  • UFW
  • Scanning the firewall
  • Quiz

10 minute break

Segment 5: User Security (30 min)

  • User & Group Security
  • su, sudo, and Passwords

Segment 6: Using SSH Properly (60 min)

  • Utilizing RSA keys
  • Timeouts, and other security best practices
  • Quiz

Segment 7: Course wrap-up (15 min)

  • Final Q&A
  • Survey
  • Ending statement