Unix and Linux books: security and system administration

Updated November 2026

A short reading list. The classics explain how Unix works and why; the newer titles cover the tools you will meet on today's systems. We have no affiliate links: buy them wherever you like, or borrow them from a library.

Security

Practical Unix & Internet Security, 3rd edition (Simson Garfinkel, Gene Spafford, Alan Schwartz)
The classic. From 2003, so the specific tools are dated, but its explanations of accounts, file systems, networks and policy are still the clearest available.
Linux Basics for Hackers (OccupyTheWeb)
A gentle introduction to Linux from the attacker's point of view: networking, processes, logging and covering tracks. Useful for defenders to understand what to look for.
Practical Linux Security Cookbook, 2nd edition (Tajinder Kalsi)
Recipe-style coverage of hardening, file system security, PAM, firewalls and auditing. From 2018, so check commands against your distribution.
SSH Mastery, 2nd edition (Michael W. Lucas)
Everything about OpenSSH: keys, agents, certificates, tunnels and hardening, in a short and readable book.

System administration

UNIX and Linux System Administration Handbook, 5th edition (Evi Nemeth, Garth Snyder, Trent R. Hein, Ben Whaley, Dan Mackin)
The standard reference for a generation of administrators. Broad, practical and opinionated.
The Practice of System and Network Administration, 3rd edition (Thomas Limoncelli, Christina Hogan, Strata Chalup)
Not about commands but about running IT well: processes, documentation, change management and dealing with users.
How Linux Works, 3rd edition (Brian Ward)
Explains what happens under the hood: boot, systemd, devices, networking and the shell. Ideal after a first course.
Absolute FreeBSD, 3rd edition (Michael W. Lucas)
The practical guide to running FreeBSD servers.

Shell and tools

The Linux Command Line, 3rd edition (William Shotts)
The best book for beginners, and it is free to read online at linuxcommand.org.
Unix Power Tools, 3rd edition (Shelley Powers, Jerry Peek, Tim O'Reilly, Mike Loukides)
A thousand tips on shells, text processing and everyday tools. Old, but most of it still works unchanged.
Classic Shell Scripting (Arnold Robbins, Nelson H. F. Beebe)
Portable shell scripting with sed, awk and friends, done properly.
The AWK Programming Language, 2nd edition (Alfred Aho, Brian Kernighan, Peter Weinberger)
Updated in 2023 by the language's authors, now including UTF-8 and CSV support.
sed & awk, 2nd edition (Dale Dougherty, Arnold Robbins)
Still the most complete treatment of both tools.

How Unix came to be

The UNIX Programming Environment (Brian Kernighan, Rob Pike)
From 1984 and still the best explanation of the Unix philosophy of small tools joined by pipes.
Advanced Programming in the UNIX Environment, 3rd edition (W. Richard Stevens, Stephen A. Rago)
The reference for system calls, processes, signals and terminals, for anyone writing C on Unix.
UNIX: A History and a Memoir (Brian Kernighan)
The story of Unix at Bell Labs, told by someone who was there.

Free books and manuals online