Understanding Linux Internals

Stop using Linux. Start understanding it. Most people who work with Linux every day never learn how it actually works. They memorize commands, copy error strings into search engines, and move on. When the same problem appears with different symptoms, they are back at square one. Understanding Linux Internals breaks that cycle. Across 12 chapters, you will trace a modern Linux system from the CPU privilege rings up through the kernel, the init system, the filesystem, the network stack, and the container runtime. Every chapter answers a real engineering question with concrete, runnable examples. You will learn: The kernel / user-space boundary — system calls, kernel threads, and why the kernel is not a process The boot sequence — UEFI, GRUB2, initramfs, systemd, and how to recover a system that will not boot Processes and scheduling — fork/exec/clone, CFS, real-time classes, CPU affinity, and cgroups Memory management — virtual memory, page tables, page faults, the page cache, swap, and the OOM killer Filesystems — VFS, ext4 and XFS, inodes, hard links, LVM, RAID, ZFS, and overlayfs Networking — the TCP/IP stack, netfilter and nftables, namespaces, and veth pairs Containers and virtualization — build a container from scratch with unshare, then run a VM with KVM and QEMU eBPF — the programmable kernel, bpftrace one-liners, and XDP Security — capabilities, AppArmor, SELinux, LUKS, Secure Boot, TPM, and seccomp Production practice — kernel upgrades, live patching, observability, and live debugging without breaking anything If you are ready to know exactly which layer produced the next error message you see, this book is your complete path from using Linux to understanding it.