SSH Mastery: OpenSSH, PuTTY, Tunnels and Keys (IT Mastery)

Mastering Linux Administration: Take your sysadmin skills to the next level by configuring and maintaining Linux systems

CompTIA Linux+ Certification Kit: Exam XK0-005

Red Hat Enterprise Linux 9 Administration: A comprehensive Linux system administration guide for RHCSA certification exam candidates

FreeBSD Mastery: ZFS (IT Mastery)

Mastering Embedded Linux Programming: Create fast and reliable embedded solutions with Linux 5.4 and the Yocto Project 3.1 (Dunfell)

Cybersecurity: The Beginner's Guide: A comprehensive guide to getting started in cybersecurity

Hands-On Network Programming with C: Learn socket programming in C and write secure and optimized network code

Absolute FreeBSD, 3rd Edition: The Complete Guide to FreeBSD

Kali Linux Hacking: A Complete Step by Step Guide to Learn the Fundamentals of Cyber Security, Hacking, and Penetration Testing. Includes Valuable Basic Networking Concepts.