This page lists free books on networking and network-related topics. The list is alphabetized by category. There’s also a section at the bottom of free vendor books.
Automation And Scripting
OpenStack Operations Guide by various
OpenStack Security Guide by various
Crypto 101 by Laurens Van Houtven (lvh)
Linux Network Security by Peter Smith
Nmap Network Scanning by Gordon “Fyodor” Lyon
TCP/IP Fundamentals for Microsoft Windows from Microsoft
Linux Network Administrator’s Guide by Olaf Kirch & Terry Dawson, from O’Reilly – sure it’s 15 years old but a) that makes it interesting in many ways (IPX people!) and b) it’s still handy where serial devices are concerned
Brocade Vyatta vRouter and BCVRE
BCVRE in a Nutshell Study Guide (Brocade Certified vRouter Engineer) – a very useful introduction to the Vyatta OS and CLI (reasonably helpful if you plan on using VyOS too)
And a number of other BCVRE resources on this page
These books are written in “book sprints” which is a commercially facilitated program to write a book in the shortest number of days. Quality is variable but these selections are well written overall.
Operating Cisco Application Centric Infrastructure (ACI) by Cisco ACI Team.
Troubleshooting Cisco Application Centric Infrastructure (ACI) by Cisco ACI Team