Boring Linux

Author

K19G

Published

October 31, 2026

Updated

October 31, 2026

Boring Linux

A detailed, progressive guide to understanding and operating Linux systems, from the first administered machine to advanced systems engineering.

The book begins with the machine, installation and boot. It develops single-host administration, storage, Linux networking and network services, security, application services, virtual machines and containers. Later parts bring those facilities together through observability, performance, automation, fleets, availability, recovery and kernel-level investigation.

Starting point

You should be comfortable opening a terminal, editing a text file and running a simple command. No prior systems-administration knowledge is assumed. New systems concepts are explained when they appear, and each practical task includes the command details needed to complete it.

Worked examples use Ubuntu 26.04 LTS as the reference environment. General Linux mechanisms are distinguished from distribution-specific packaging, policy and defaults. Other distribution behavior is explained where it changes the administrative task.

How to learn

Follow the parts in order on the first pass. Each subject connects its mechanism to configuration, observation, operation, diagnosis and recovery. Diagrams show relationships; worked examples explain input, output and the limits of an observation. Labs provide results you can verify, and recall cards support later reference.

The opening inspection examples can be studied before building the lab VM. Repeat them on that VM after completing the lab-building chapter. Configuration and recovery experiments belong in the designated disposable lab.

Current writing progress

The syllabus has been rebuilt and writing has restarted. Part 01 currently contains eight complete chapters:

  1. What Linux Consists Of

  2. Hardware, Firmware and Virtual Machines

  3. CPU, Memory, Storage and Network Resources

  4. System Paths, Configuration and State

  5. Processes, Services and Sessions

  6. Distributions, Releases and Documentation

  7. Building the First Virtual Machine

  8. Inventory, Evidence and First Troubleshooting

Part 02, Installing and Provisioning Linux, now contains eight chapters:

  1. Installation Media, Authenticity and Integrity
  2. Planning Firmware, Storage, Identity and Networking
  3. Guided Installation and the Resulting Storage Layout
  4. Manual Storage Choices, Encryption and Swap
  5. First Boot: Administrative Access, Updates and Service Inventory
  6. Hardware and Virtual-Device Discovery
  7. Image-Based and Unattended Installation
  8. Reinstallation and Host Configuration Recovery

Part 03, Boot, Shutdown and Recovery, begins with:

  1. Firmware, UEFI Variables, GPT and the EFI System Partition
  2. Bootloader Selection: GRUB and systemd-boot
  3. Kernel Images, Command Lines and Matching Modules
  4. Initramfs and Reaching the Real Root
  5. Root Handoff, PID 1 and the Boot Transaction
  6. Targets, Activation, Readiness and Boot Timing
  7. Shutdown, Reboot and Services That Delay Shutdown
  8. Secure Boot, Unified Images and Measured Boot
  9. Rescue, Emergency and External-Media Recovery
  10. Offline Inspection, Chroot Repair and the Next Normal Boot

Part 04, Users, Identity and Administrative Access, contains:

  1. UIDs, GIDs, Groups and Ownership
  2. Account Databases, NSS and Identity Lookup
  3. Account Creation, Locking, Expiration and Removal
  4. Home Directories, Skeletons and Session Environments
  5. Passwords, Credential Storage and Policy
  6. PAM Stacks and Diagnosing Login Failures
  7. Administrative Privilege and Bounded Delegation
  8. Service Accounts and Runtime Credentials
  9. Sessions, logind and Authorization Beyond the Terminal
  10. Central Identity: LDAP, Kerberos and SSSD Foundations

Part 05, Packages, Software and Updates, is complete:

  1. Package Metadata, File Ownership and Installed State

  2. dpkg, APT and Dependency Resolution

  3. Repositories, Signatures and Source Configuration

  4. Version Selection, Holds, Pinning and Dependency Conflicts

  5. Configuration Files, Alternatives and Package Hooks

  6. Security Updates and Maintenance Windows

  7. Kernel Updates, Reboots and Livepatch

  8. Snaps, Flatpak and Other Software Formats

  9. Source Builds, Local Packages and Reproducibility

  10. Offline Repositories, Mirrors and Disconnected Installation

  11. Interrupted Package Transactions and Recovery

Part 06, Services, systemd and Scheduled Work, begins with:

  1. Service Supervision, Units and Managers
  2. Execution Environment, Identity and Exit Status
  3. Startup Types, Readiness, Watchdogs and Restarts
  4. Requirements, Ordering and Failure Propagation

The following map is the planned curriculum. Later parts are added to the chapter tree as they are written.

Curriculum map

Part Subject
01 The Linux Machine and the Administration Lab
02 Installing and Provisioning Linux
03 Boot, Shutdown and Recovery
04 Users, Identity and Administrative Access
05 Packages, Software and Updates
06 Services, systemd and Scheduled Work
07 Processes, Memory and Resource Administration
08 Configuration, Devices, Time and Local Logs
09 Disks, Partitions and Filesystems
10 Volumes, RAID, Encryption and Storage Health
11 Backup, Restore and Data Lifecycle
12 Linux Host Networking
13 DNS, Address Assignment and Time Services
14 Remote Access, Certificates and Trust Services
15 Linux Gateways, Firewalls and Virtual Networks
16 File, Storage and Messaging Services
17 Linux Access Control and Isolation
18 Hardening, Secrets, Audit and Security Response
19 Web, Application and Data Services
20 Virtualization and Virtual Machine Operations
21 Containers and System Containers
22 Kubernetes and Linux Cluster Workloads
23 Troubleshooting and Observability
24 Performance and Capacity Engineering
25 Provisioning and Configuration Automation
26 Fleet Maintenance and Software Delivery
27 High Availability and Shared Infrastructure
28 Reliability, Incidents and Disaster Recovery
29 Advanced Linux Architecture and Kernel Internals
30 Tracing, eBPF and Failure Analysis
31 Specialist Linux Systems
32 Integrated Systems Engineering Projects
33 Running Multiple Kernels on One Bare-Metal Server
34 Linux Performance Engineering & Server Benchmarking
35 A Practical Guide to Securing Linux from Kernel to Cloud
36 The ext4 Filesystem: Architecture, Internals, and Implementation
37 A Complete Guide to Virtual Memory, Allocators, Paging, and Performance in the Modern Linux Kernel
38 Ubuntu 26.04 LTS: From Desktop to Enterprise Cloud

Specialist branches include multikernel bare-metal architectures, performance engineering and production benchmarking, enterprise security and hardening from kernel to cloud, filesystem engineering and on-disk internals, desktop/session infrastructure, hardware and accelerators, cloud hosts, edge systems and disconnected environments. Each identifies its prerequisites so the main progression remains usable without specialized equipment.