Master Linux networking from the ground up. This book is a practical, systems-first guide that equips you with the tools and expertise to design, build, and operate Linux-first network infrastructure with confidence. You will learn both the underlying principles and the hands-on implementations that make robust, scalable networks possible.
The book begins by establishing strong mental models: the OSI and TCP/IP stacks; IPv4/IPv6 addressing, subnetting, and CIDR; and the core protocols that underpin them (TCP, UDP, ICMP, and ARP). It then maps these concepts to Linux primitives—kernel networking, netdevices, network namespaces, netfilter, and conntrack—before moving into host-level implementations and foundational network services. Troubleshooting and observability are treated as first-class skills, with a practical toolkit centered on tcpdump, tshark, ip, ss, mtr, netcat (nc), and nmap.
Security and routing form the heart of the book's advanced material. The chapters cover host firewalls in depth, starting with iptables and progressing to modern, production-grade nftables. You will learn advanced routing techniques—policy-based routing (PBR) and Virtual Routing and Forwarding (VRF)—that turn a Linux host into a production-ready router.
The book then turns to dynamic routing, showing how Linux runs OSPF and BGP and participates in Internet-scale routing through the open-source FRR suite. Operational concerns in large networks are addressed with protocols and patterns such as BFD, ECMP, and VRRP. Finally, you will learn to secure connectivity, from VPN fundamentals to end-to-end guides for IPsec (strongSwan/Libreswan), OpenVPN, and WireGuard.
By the end, you will have a deep understanding of Linux networking internals and the practical skills to architect, harden, and operate complex networks across cloud, on-premises, and edge environments.

What You Will Learn
•    Understand the core design principles that modern, cloud-native networks are built on
•    Convert Linux hosts into production-grade routers using the kernel's routing subsystem, policy routing, and VRFs
•    Diagnose tricky real-world behavior, including asymmetric routing, reverse path filtering, and connection tracking
•    Connect sites, remote users, and data centers with VPN solutions such as IPsec and WireGuard

Who This Book is For 
Cloud Engineers, Infrastructure Architects, Platform Engineers and Architects, Data Center Architects, Network Engineers and Architects

Safeer CM has worked in site reliability, DevOps, and platform engineering for the past 20 years. He is the author of the book Architecting Cloud-Native Serverless Solutions. He was an ambassador for the Continuous Delivery Foundation from 2022 to 2025. He has been a speaker at multiple conferences, including KubeCon India 2025, writes blogs, and has been editor, curator, and organizer for different conferences and meetups. Currently, he is working as a Principal Engineer at MoEngage. In the past, he has worked at Yahoo, LinkedIn, Flipkart etc, where he built and managed large-scale infrastructures.

Sreejith Anujan is a Principal Learning Architect at Red Hat with over 20 years of industry experience and deep-rooted expertise in Linux and open-source technologies. He specializes in cloud native platforms, containerization, and automation tooling, designing and implementing DevOps and platform engineering solutions using Ansible, CI/CD pipelines, and GitOps workflows. Alongside solution design, he enables clients through technical workshops and tailored enablement programs. With certifications across AWS, Azure, Red Hat, VMware, and the Linux Foundation, Sreejith combines technical depth with a passion for teaching. He also contributes actively to the community, organizing DevOpsDays Kerala and Kubernetes Community Days Kerala.