everything about linux distros
The previous two chapters covered troubleshooting as a method and as a catalog of common scenarios. This chapter applies both. Deploying a web server is one of the first real tasks a new system administrator performs, and it exercises nearly every competency the LFCA exam tests: package management, service management, network configuration, file permissions, and…
User and group management is the quiet foundation of every Linux system. Before a service can run, before a file can be shared, before anyone can log in, the system must know who exists, what groups they belong to, and what they are allowed to do. This is not glamorous work. It rarely makes headlines….
A backup that has never been restored is not a backup. It is a hope. This chapter walks through setting up a backup system on a Linux host, but it treats the restore as the point, not an afterthought. You will create archives with tar, synchronize file trees with rsync, schedule automated runs, and—critically—verify that…
A network problem is a mystery with layers. The user reports that “the internet is down.” The application logs show connection timeouts. The monitoring system fires an alert about packet loss. Each of these symptoms is real, but none of them tells you where the problem actually lives. Is it the cable? The interface? The…
Containers are not virtual machines. A container is a process—or a small group of processes—running on the host kernel, isolated by namespaces and constrained by cgroups. This distinction matters for the deployment workflow. There is no boot sequence, no init system, no hypervisor. A container starts in milliseconds, runs until its main process exits, and…
The LFCA exam was updated on September 16, 2025. The domains remained the same, but the competencies within each domain were adjusted. If you sit for the exam after that date, the updated objectives apply regardless of when you purchased the exam . This chapter is a structured review of the six domains, their weights,…
The LFCA exam asks 60 multiple-choice questions in 90 minutes. Domain 1, System Administration Fundamentals, is the heaviest domain at 30% of the exam—roughly 18 questions. It covers user and group management, file permissions, process and service management, networking fundamentals, troubleshooting methodology, and disaster recovery. These are the questions where practical familiarity with commands matters…
Domain 2, Linux Fundamentals, is 16% of the LFCA exam—roughly 10 questions. It covers the Linux operating system itself: distributions and their package managers, the Filesystem Hierarchy Standard, open source licensing, and the command line. These are the questions that test whether you understand how Linux is organized, not just how to run commands. This…
Domain 3, Cloud Computing Fundamentals, is 18% of the LFCA exam—roughly 11 questions. It is the second-largest domain, and it is entirely conceptual. There are no commands to memorize, no configurations to build. The questions test whether you understand what the cloud is, how it is delivered, how it is deployed, and how it is…
Domain 4, Security Fundamentals, is 14% of the LFCA exam—roughly 8 questions. It covers the concepts that underpin security in modern IT: the CIA triad, authentication and authorization, encryption, firewalls, compliance, and common threats. These are conceptual questions. There are no commands to memorize, no configurations to build. The exam tests whether you understand the…