Downloading the OS installation file

In this section, we will cover the process of downloading the Linux server operating system, including which Linux distributions are recommended and the requirements that need to be met.

When it comes to choosing a Linux distribution for your server, there are many options to choose from. Some popular choices include Ubuntu, Debian, and Red Hat. However, one of the most popular and stable choices for enterprise and web server environments is the Community Enterprise Operating System (CentOS).

CentOS is a free and open source Linux distribution based on Red Hat Enterprise Linux (RHEL). It is known for its stability and reliability, making it a popular choice for enterprise and web server environments. It is also widely used in the hosting industry, education, research, and for personal use. It is compatible with the Red Hat ecosystem, meaning that users can leverage their existing knowledge, skills, and tools of RHEL. The distribution is maintained by a large community of developers and users who work together to provide updates and security patches, making it a secure and stable choice. Additionally, it is designed to be fully compatible with the upstream vendor, Red Hat, and it provides an almost identical environment. This means that users can use the same set of commands and packages as in Red Hat Linux, and they can also access the Red Hat customer portal and support. As we’ll be making use of CentOS throughout this book, we’ll be downloading the installation image from the official website (https://www.centos.org/). The website offers both DVD and minimal ISO images, which can be used to install the server. Make sure to download the correct version for your architecture (32-bit or 64-bit).

When it comes to downloading the installation image for CentOS 8, there are two options available:

• CentOS-Stream-8-x86_64-20220104-boot.iso
• CentOS-Stream-8-x86_64-20220104-dvd1.iso

The CentOS-Stream-8-x86_64-20220104-boot.iso file is a minimal image used for booting the system and performing a network installation. It is designed to be used with a network-based installation process and contains only the packages required to start the installation process. Additional files will be downloaded during the installation.

The CentOS-Stream-8-x86_64-20220104-dvd1.iso file is the DVD image containing all the packages included in the distribution. It can be used for a local installation (also known as an offline installation, as there is no need to download files during the installation), and it contains a complete set of packages.

It’s important to note that, depending on your system requirements and the intended use of the server, one of these images may be more suitable than the other. The minimal image is recommended for servers with limited resources, while the DVD image is recommended for servers with more resources and a wider range of needs. The following are the system requirements for setting up our own server:

• Processor: A 64-bit processor is required
• Memory: A minimum of 2GB of RAM is recommended, but 8 GB or more is recommended for servers with a high workload
• Disk space: A minimum of 20 GB of storage space is recommended, but the more storage space, the better
• Network connectivity: A network connection is required for downloading the installation image and performing updates
• Graphics card: A graphics card is not necessary for a server, but if you’re planning on using the server for graphical applications, a graphics card is recommended
• Operating system: A 64-bit version of Windows, macOS, or Linux is required for running a hypervisor

Now that we know our system requirements, our first step is to open a web browser and go to www.google.com:

1. In the search bar, type download CentOS ISO and press Enter. This will bring up the official website for CentOS, which is https://www.centos.org/ (see Figure 1.1).

Figure 1.1 – Google search

2. Our second step is to select the x86_64 option for all architectures:

Figure 1.2 – x86_64 architectures

3. Next, we select the available link for our region. As we can see from the figure, mine is http://mirror.web4africa.ng/centos/8-stream/isos/x86_64/:

Figure 1.3 – Selection by region

From the index /centos/8-stream/isos/x86_64/, we’ll need to download the CentOS-Stream-8-x86_64-20221222-dvd1.iso DVD version. As we have read previously, the DVD image contains all the packages that are included in the distribution, which means that it can be used to perform a local installation.

Figure 1.4 – DVD download page

After downloading the image, we’ll need to download a hypervisor.