This book is for readers who already have some experience with Linux, though it doesn't necessarily have to be with Ubuntu. Preferably, the reader will understand basic Linux command-line skills, such as changing directories, listing contents, and issuing commands as regular users or with root. Even if you don't have these skills, you should read this book anyway—the opening chapters will cover many of these concepts.

In this book, we'll take a look at real-world situations in which we can deploy Ubuntu Server. This will include the installation process, serving web pages, setting up databases, and much more. Specifically, the goal here is to be productive. Each chapter will teach the reader a new and valuable concept, using practical examples that are relative to real organizations. Basically, we focus on getting things done, not primarily on theory. Although the theory that goes into Linux and its many distributions is certainly interesting, the goal here is to get you to the point where if a work colleague or client asks you to perform work on an Ubuntu-based server, you'll be in a good position to get the task done. Therefore, if your goal is to get up and running with Ubuntu Server and learn the concepts that really matter, this book is definitely for you.

To follow along, you'll either need a server on which to install Ubuntu Server, a virtual Ubuntu instance from a cloud provider, or a laptop or desktop capable of running at least one virtual machine.

There are a number of text conventions used throughout this book.

CodeInText: Indicates code words in text, database table names, folder names, filenames, file extensions, pathnames, dummy URLs, user input, and Twitter handles. Here is an example: "I added an IP address of 192.168.0.101 with a CIDR mask of /24."

A block of code is set as follows:

# This file describes the network interfaces available on your system
# For more information, see netplan(5).
network:
  version: 2
  renderer: networkd
  ethernets:
    enp0s3:
      dhcp4: yes

When we wish to draw your attention to a particular part of a code block, the relevant lines or items are set in bold:

# This file describes the network interfaces available on your system 
# For more information, see netplan(5). 
network: 
  version: 2 
  renderer: networkd 
  ethernets: 
    enp0s3: 
      dhcp4: no 
     addresses: [192.168.0.101/24] 
     gateway4: 192.168.1.1 
     nameservers: 
       addresses: [192.168.1.1,8.8.8.8] 

Any command-line input or output is written as follows:

sudo ip link set enp0s3 down 
sudo ip link set enp0s3 up 

Bold: Indicates a new term, an important word, or words that you see onscreen. For example, words in menus or dialog boxes appear in the text like this. Here is an example: "At this point, you'll click Select image, which will open up a new window that will allow you to select the ISO file you downloaded earlier. Once you select the ISO, click on Open."