System Administration

Installing Enterprise Linux

In this post I’m going to demonstrate the installation of Enterprise Linux in VMware.

I’ll be installing the AlmaLinux distribution because it’s a completely free, community maintained Enterprise distribution, though the steps outlined here should be the same for all variants of Red Hat Enterprise Linux, including Oracle Linux, Rocky Linux and CentOS.

First of all, download the AlmaLinux installation ISO from the official website. I’ll be installing version 8.6 for x86_64. You can select any of the iso images, for example the DVD iso contains the entire distribution at 10GB, alternatively I’ll be selecting the boot iso as it’s a smaller initial download and I don’t need every package that comes in the full DVD.

You should also have either VMware or similar Virtual Machine software installed. I’ll be using VMware workstation player as it’s free for home use, but you could also just as easily use VirtualBox. The installation steps covered below will also work if you’re installing Linux on a bare metal PC.

Open VMware and select “Create a New Virtual Machine”.

You’ll then need to select the ISO image that you downloaded. Select the second option “Installer disk image” and click “browse” to find the iso.

Click Next to continue.

On the next screen VMware auto-detected that I was installing a Red Hat Linux variant, which is correct so we can click Next to continue.

In the next screen you can give your virtual machine a name, I chose AlmaLinux 8, because I’m super creative, but you can name it anything you like. Leave the Location at the default unless you have a reason to move it.

On the next screen you’re asked to specify disk capacity. This is to set the size of the virtual machine hard disk that you’ll be installing to. I’m going to leave mine at the default 20GB.

On the final screen, confirm that all the settings are correct and click Finish.

Once the virtual machine has been created you can click the “Play virtual machine” button to start up the installation process. Once the machine boots up you will be presented with the “Welcome to AlmaLinux” screen. Select your language if you need to change the default and click Continue.

On the Installation Summary screen you’ll likely see a bunch of red messages. This is fine and completely normal, it’s just the installation process letting you know what you still need to configure before continuing with the installation.

Select the Network & Host Name option first. If your Host PC is connected to the Internet, which I’m assuming it is as you’re reading this, you should just be able to toggle the Ethernet button to On and the network should auto-connect.

If you want to also give your machine a Hostname instead of locahost.localdomain this is where you can do that. I’m not going to that here as it’s easy to change later. Click Done.

Next, if Installation Source is still red you will have to configure that. This is to decide where the packages will be installed from. If you downloaded the full DVD iso then you can likely ignore that and just install from the local source, but if like me you downloaded the boot iso you might need to select the remote location to download the rest of the packages from. AlmaLinux should pick a mirror automatically once the network is connected, but if it doesn’t you’ll need to search online for your closest mirror URL.

Next select Software Selection. This screen is to actually pick which packages or package groups to install.

I’m going to pick “Server with GUI” though feel free to pick an environment that suits your purposes.

In most production environments you’ll likely not encounter a Linux server with a GUI so feel free to not pick the GUI selection if you prefer, however for the purposes of a test environment like I’m installing, a GUI is fine.

I’d like to mention though, if you’re preparing this installation to study for an Enterprise Linux certification, such as RHCSA, some exam questions may require the GUI to perform certain tasks.

Next you’ll need to configure the Installation Destination. This is to prepare the virtual hard drive (or the physical hard drive if you’re installing this on bare metal) for the file system.

By default AlmaLinux will configure Logical Volume Manager (LVM) and use the entire disk, which is normally fine, however for the purposes of this installation I’m going to use a custom configuration. Select “Custom” under Storage Configuration and click Done.

In the Manual Partitioning screen you’ll have to configure how you want to partition your storage disk. If you’re unsure of what partitions are, it’s essentially a way to divide up your hard disk for Linux to be installed onto. Disk partitioning is a huge and sometimes confusing topic, which if you’re on the path to becoming a Linux System Administrator it’s worth spending some time to understand it.

We want to create 3 basic partitions to install Linux onto. A small /boot partition that stores the essential boot files such as the bootloader and the Linux kernel, we also want a large root partition that will store the rest of the operating system, and then a swap partition that Linux uses for temporary memory (RAM) if your computers physical RAM is being used.

The reason I wanted to manually configure these partitions rather than sticking with the default, is because I want to leave a bit of spare disk space (unpartitioned) for later use. In most use cases this isn’t necessary, but later on I want to play around with resizing partitions using LVM so leaving some disk space makes this easier rather than creating additional virtual hard disks and mounting them, which is also a valid option. In fact, I might do that later anyway.

So to set up the 3 basic partitions, leave LVM selected as the partitioning scheme and select the + button.

When ‘Add a new mount point” appears, first select /boot and allocate 500MiB as desired capacity. Select ‘Add mount point’.

Click the + button again and from the dropdown select the / and allocate 10GiB.

Finally, select + again and choose swap and 1GiB.

Your screen should look something like this, showing 8.5GiB available space on a 20GiB storage device.

Select Done and then Accept Changes.

Finally you’ll need to set a Root password for your administrator account and it’s recommended to also create a non-root user as your standard login account.

When creating a standard user account, make sure to select “Make this user administrator” which will add your user account to the “Wheel” group allowing you to perform administrative tasks without logging in directly as root. Click done.

That should be the final configuration step you need to perform. If there is no more red text on the Summary screen you can click “Begin Installation” to continue. Depending on whether you’re installing from the DVD iso or over the network and considering the software packages you chose to install and your Internet speed, the actual installation process might take a while.

Once the installation is complete you can reboot the machine.

Before you can use your new installation you’ll need to accept the license information and click Finish Configuration.

Login as your non-root user.

Personally, I prefer the Gnome Classic desktop environment, which you can select from the gear icon under the password field on the login screen.

Congratulations and enjoy Enterprise Linux.