Linux Administration Best Practices

Practical solutions to approaching the design and management of Linux systems

Scott Alan Miller

• Publisher: Packt Publishing
• Year: 2022
• ISBN:
  9781800565760
• Edition: 1
• Topic: Informatique
• Subtopic: Systèmes d'exploitation

Gain an understanding of system administration that will remain applicable throughout your career and understand why tasks are done rather than how to do themKey Features• Deploy, secure, and maintain your Linux system in the best possible way• Discover best practices to implement core system administration tasks in Linux• Explore real-world decisions, tasks, and solutions involved in Linux system administrationBook DescriptionLinux is a well-known, open source Unix-family operating system that is the most widely used OS today. Linux looks set for a bright future for decades to come, but system administration is rarely studied beyond learning rote tasks or following vendor guidelines. To truly excel at Linux administration, you need to understand how these systems work and learn to make strategic decisions regarding them. Linux Administration Best Practices helps you to explore best practices for efficiently administering Linux systems and servers. This Linux book covers a wide variety of topics from installation and deployment through to managing permissions, with each topic beginning with an overview of the key concepts followed by practical examples of best practices and solutions. You'll find out how to approach system administration, Linux, and IT in general, put technology into proper business context, and rethink your approach to technical decision making. Finally, the book concludes by helping you to understand best practices for troubleshooting Linux systems and servers that'll enable you to grow in your career as well as in any aspect of IT and business. By the end of this Linux administration book, you'll have gained the knowledge needed to take your Linux administration skills to the next level.What you will learn• Find out how to conceptualize the system administrator role• Understand the key values of risk assessment in administration• Apply technical skills to the IT business context• Discover best practices for working with Linux specific system technologies• Understand the reasoning behind system administration best practices• Develop out-of-the-box thinking for everything from reboots to backups to triage• Prioritize, triage, and plan for disasters and recoveries• Discover the psychology behind administration dutiesWho this book is forThis book is for anyone looking to fully understand the role and practices of being a professional system administrator, as well as for system engineers, system administrators, and anyone in IT or management who wants to understand the administration career path. The book assumes a basic understanding of Linux, including the command line, and an understanding of how to research individual tasks. Basic working knowledge of Linux systems and servers is expected.

Section 1: Understanding the Role of Linux System Administrator

The objective of Section 1 is to help you to comprehend the scope, responsibilities, role, and mandate of the System Administrator function. We take the reader past the concept of tasks and really attempt to dig into the purpose and value of the role at a much deeper level.

This part of the book comprises the following chapters:

• Chapter 1, What Is the Role of a System Administrator?
• Chapter 2, Choosing Your Distribution and Release Model

Chapter 1: What Is the Role of a System Administrator?

Few things in our industry sound like they should be simpler to answer than this one, simple question: what is a system administrator? And yet, ask anyone and you'll get some widely differing opinions. Everyone seems to have their own take on what the title or role of System Administrator implies, including and possibly most varying in people who use this title for themselves or from the companies that hand it out!

Welcome to system administration and specifically Best Practices of Linux Administration. In this chapter we are going to dive into understanding the job, role, and functions of a real system administrator and try to understand how we, in that role, fit into an organization.

In tackling this book, it is necessary both for myself to have some semblance of a clear course in writing, but also for you to understand if this book is for you, or to grasp the scope that I am attempting to cover, for me to clearly define what a system administrator is to me.

Understanding exactly what is expected of a true system administrator will be the foundation for applying that definition of the role to the upcoming best practices that apply both to system administration generally and specifically to Linux administration.

In this chapter we are going to cover the following main topics:

• Where are system administrators in the real world
• Wearing the administrator and engineering hats
• Understanding systems in the business ecosystem
• Learning system administration
• Introducing the IT professional

Where are system administrators in the real world?

I think that one of the most challenging things about attempting to understand what a system administrator is comes from the fact that the title of system administrator is often given out, willy nilly, by companies with little to no understanding of Information Technology (IT), systems, or administration and treat it like a general filler for IT roles that they do not understand or know how to name. It also has a strong tendency to be given out in lieu of pay raises or promotions to entice junior staff to remain in an otherwise unrewarding job in the hopes that an impressive title will help them later in their career, so much so that in the end, the number of people working as system administrators is a very small number of people compared to the number of people with the title. In fact, it is no small stretch to guess that the average person with the title of system administrator has never thought about the meaning of the title and may have little inkling of what someone in that role would be expected to do.

If we look solely by title, system administrators are everywhere. But they exist mostly at companies too small to have plausibly employed a system administrator at all. Systems administration as a dedicated job is nearly exclusive to large companies. Most companies need someone to do the tasks of system administration, but only as a part of, and often only a small part of, their overall duties. It is the nature of IT that in small and medium sized companies you typically have generalists who wear many hats and do every needed IT role while having little to no time to focus on any one specific function. Whereas in large enterprises you generally get focused roles, often grouped into focused departments, that do just a single IT role: such as system administrator. But even in some enterprises you find departments organized like separate, small businesses and still having generalists doing many different tasks rather than separating out duties to lots of different people.

There is nothing wrong with this, of course. It is totally expected. It's much like how, as a homeowner, you will often do a lot of work on the house yourself, or you might hire a handyman who can do pretty much whatever is needed. You might need some plumbing, painting, carpentry, wiring, or whatever done. Whether you do it yourself, or your handyman does, you do not refer to either of yourselves as plumbers, painters, carpenters, and others. You are just a handy person, or the person that you hired is. You still recognize that a dedicated, full time, focused plumber, painter, carpenter, or electrician is a specialized role. You might do all those tasks occasionally, you might even be good at it, but it's not the same as if that was your full-time career. If you decided to claim to be these things to your friends, they would quickly call you out on the fact that you are quite obviously not those things.

System administrators are like plumbers. Everyone who owns a house does at least a little plumbing. A handyman who does home maintenance full time might do a fair amount of plumbing. But neither is a plumber. A very large housing development, or a construction crew might have a dedicated plumber on staff. Maybe even more than one. And nearly every homeowner must engage one from time to time. If you are me, regularly. Most plumbers either work for large companies that have need of continuous plumbing services or they work for plumbing contracting firms and have the benefits of peers and mentors to help them advance in their knowledge.

Nearly every business no matter what size we are talking about needs system administration tasks done. For very small businesses it is not uncommon for these tasks to amount to no more than a few hours per year, and when needed the scheduling is often unpredictable with many hours needed all at once and large gaps of time in which nothing is needed. In large businesses, you might need tens of thousands of hours of system administration tasks per week and require entire departments of dedicated specialists. So just like plumbers, you find small businesses either hiring IT generalists (akin to the homeowner's handyman) or outsourcing system administration tasks to an outside firm like an Managed Service Provider (commonly referred to as an MSP) or keeping a consultant on retainer; and you will find large companies typically hiring full time specialist system administrators that do nothing else and work only for that firm.

System administration tasks exist in every business, in every industry and create the foundation of what I feel is one of the most rewarding roles within the IT field. With system administration skills you can chart your own course to work in a large firm, be a consultant, join a service provider, or enhance other skills to make yourself a better and more advanced specialist. Without a firm foundation in system administration a generalist will lack one of the most core skills and have little ability to advance even in the generalist ranks. And at the top of the generalist field, true CIO roles primarily pull from those with extensive system administration comprehension.

At this point we know what a system administrator is, where you will find them in businesses, and why you might want to pursue system administration either as your career focus or as an enhancement to a career as a generalist. Now we can go into real detail about what a system administrator really does!

Wearing the administrator and engineering hats

In this section, we will explore two parts:

• How does administration and engineering differ.
• How to identify the role you are performing.

The name system administrator itself should clue us in as to what the role should entail. The title is not meant to be confusing or obfuscated. Yet many people believe that it is some kind of trick. If you spend enough time working in the small business arena you might even find that many people, people who are full time IT professionals, may not even believe that true system administrators exist!

System is a reference to operating system and designates the scope of the role: managing the platform on which applications run. This differentiates the system administrator role from, say, a database administrator (commonly called a DBA) who manages a database itself (which runs on top of an operating system), or an application administrator (who manages specific applications on top of an operating system), or a platform administrator (who manages the hypervisor on which the operating system runs), or a network administrator (who manages the network itself.) Being called a system administrator should imply that the focus primarily or nearly entirely of the person or role is centered around the care and feeding of operating systems. If your day isn't all about an operating system, you aren't really a system administrator. Maybe system administration is part of your duties but being a system administrator is not the right title for you.

Administrator tells us that this role is one that manages something. The direct alternative to an administrator is an Engineer. An engineer plans and designs something; an administrator runs and maintains something. I often refer to these roles as the A&E roles and often the titles are used loosely and meaninglessly based on how the speaker thinks that it will sound. But, when used accurately, they have very definite meanings and in each area within IT (systems, platforms, network, databases, applications, and others.) you have both working in concert with one another. Of course, it is exceptionally common to have one human acting as both an engineer and an administrator within an organization, the roles have extensive overlap in skills and knowledge and necessarily must work in great cooperation to be able to do what they do effectively.

The difference between the role of an administrator and the role of an engineer

There is a key difference between the two roles, however, that impacts organizations and practitioners in a very meaningful way, which is very important to discuss because otherwise, we are tempted to feel that separating the two roles is nothing more than pedantic or a game of semantics. This difference is in how we measure performance or success.

An engineering role is measured by throughput or the total quantity of work done. It's all about productivity – how many systems the engineering team can design or build in a given period of time.

The administrator role would make no sense in this same context. Administrators manage systems that are already running rather than implementing new ones. An administrator is measured on availability, rather than productivity. This may sound odd to hear, but this is mostly because the average organization has little to no understanding of administration and has never contemplated how to measure the effectiveness of an administration department.

Hats

I spend a lot of time talking about hats. Understanding hats is important.

By hats, I mean in the sense of the different job roles that we take on and understanding when we are performing the tasks of one role or another – referred to as wearing a hat. For example, if I work in a restaurant I might act as a waiter one day and we would say that I was wearing a waiter hat. The next day I might be working in the kitchen making salads and then I would be wearing the short order cook hat.

This may sound a bit silly, but it is important to understand. The term hats tends to allow us to understand the difference between being a thing and performing the actions associated with that thing better. We all know what is required to be a plumber, but most plumbers drive trucks to their job sites. Does this make them truck drivers? Is the skill of driving a truck actually part of the skill of plumbing? No, it is not. But it is a generally useful ancillary skill. But a large plumbing company could easily co...