Learning AlmaLinux - Installation & Deployment

#Introduction

In the previous episode, Episode 2, we broke down AlmaLinux's architecture: how the rebuild is built from RHEL SRPMs, its main components, and the repositories that make it up. Now it's time to take real action: installing AlmaLinux on your machine. This episode guides you from booting the installer to a ready-to-use system, then opens the door to the automated deployment that is standard in the modern world.

Installation might look like a one-time task, but the decisions you make here — software set, partitioning, and boot options — determine the system's character for years to come. Let's do it right from the start.

#The Anaconda Installer

Anaconda is the official installer of the Red Hat family. It's available in three modes you can choose based on your needs:

Mode	Use
Graphical	The default mode with a full visual interface; easiest for beginners
Text	A terminal-based mode; lightweight and suitable for remote installation
Kickstart	A fully automated mode based on a configuration file; for mass provisioning

Main Anaconda installer steps

1. Language & keyboard
2. Installation destination (partitioning)
3. Software selection (software set)
4. Root password & user creation
5. Network & hostname
6. Begin installation

#Choosing a Software Set

One of the most important decisions is the software set — the default packages that get installed. Anaconda provides several options:

Software Set	Characteristics
Server with GUI	Full server plus desktop; wasteful for production
Server	Server without a desktop; the main production choice
Minimal	Only the most basic packages; lightest and most secure
Workstation	Full desktop for end users

Tip

For this series, choose Minimal or Server. A system with fewer packages is more secure (smaller attack surface), and you'll install the tools you need per episode step by step — exactly like a production sysadmin does.

#Partitioning: LVM, Btrfs, and Encryption

The partitioning step determines how your storage is organized. Anaconda provides automatic and manual schemes.

#LVM (Logical Volume Manager)

LVM is the default and most popular scheme. It separates physical storage (/dev/sda) from logical storage (volumes), so partitions can be resized easily without replacing hardware. Its basic structure:

PV (Physical Volume) — a physical disk or partition.
VG (Volume Group) — a collection of PVs pooled into one storage pool.
LV (Logical Volume) — logical partitions carved from the VG, where filesystems and mount points are attached.

#Btrfs and Encryption

Btrfs — a modern filesystem with snapshot and copy-on-write features. Starting with AlmaLinux 9, Btrfs can be selected directly as the default partition layout.
Encrypted partitions — use LUKS to encrypt the disk contents. A must-consider for laptops and servers storing sensitive data.

View the partition structure after install

lsblk

#Secure Boot and UEFI

Modern systems boot through UEFI (the replacement for the old BIOS), and Secure Boot verifies the signature of every boot component so no malware can hijack the boot process. AlmaLinux fully supports Secure Boot: its installer images and kernels are already signed, so it can boot on machines with Secure Boot enabled.

Check the boot mode after install

[ -d /sys/firmware/efi ] && echo "UEFI mode" || echo "Legacy BIOS mode"

Warning

If your machine uses UEFI, make sure the boot mode in the firmware matches (UEFI, not Legacy/CSM). Mixing the two often causes the system to fail to boot or the EFI System Partition not to be created.

#Automated Deployment: Kickstart

After mastering interactive installation, it's time to automate. Kickstart is a configuration file that answers all the installer's questions automatically — so thousands of servers can be installed with identical results and no human interaction.

#Kickstart File Structure

Kickstart from a previous install

# Kickstart file generated by Anaconda
lang=en_US.UTF-8
keyboard --vckeymap=us
network --bootproto=dhcp --device=ens192
rootpw --iscrypted <hash>
user --name=devops --groups=wheel
%packages
@server
openssh-server
%end

%packages — the list of packages and groups to install, ending with %end.
%post — scripts run after installation completes, suitable for additional configuration such as installing a monitoring agent or creating users.

An interactive installation automatically produces a Kickstart file at /root/anaconda-ks.cfg — use it as the starting template for your Kickstart files. To validate files you write, install pykickstart, which provides a validator:

Validate a Kickstart file

sudo dnf install -y pykickstart
ksvalidator /root/anaconda-ks.cfg

Once the file is valid, run the installer by adding inst.ks=<file-location> to the boot parameters, for example inst.ks=http://192.168.1.10/ks.cfg to source it from a network server.

#Deploying with Cloud Images

For modern cloud and virtualization environments, installing through Anaconda is usually not the option. Instead, use cloud images that are already configured for automated provisioning.

#cloud-init

cloud-init is the industry standard for provisioning cloud instances. Every AlmaLinux cloud image already includes it. When an instance first boots, cloud-init reads configuration from two sources:

metadata — the instance's identity data (hostname, instance ID, network).
user-data — the configuration you provide (users, SSH keys, packages to install).

user-data for cloud-init

#cloud-config
users:
  - name: devops
    sudo: ALL=(ALL) NOPASSWD:ALL
    ssh_authorized_keys:
      - ssh-ed25519 AAAA... user@host
package_update: true
packages:
  - git
  - htop

#Other Images: WSL and Raspberry Pi

Besides the cloud, AlmaLinux also provides images for special environments:

WSL — run AlmaLinux inside Windows Subsystem for Linux without a separate VM.
Raspberry Pi 4/5 — an ARM64 image for Raspberry Pi devices, great for home servers and IoT labs.

#Verifying the Installation

After the system's first boot, run the following verification to make sure the installation is clean:

Verify the new system

cat /etc/os-release
lsblk
free -h
dnf5 --version

Warning

Run sudo dnf5 upgrade right after installation finishes. The installer only carries the state of the ISO at release time; after that, many security updates need to be pulled from the repositories.

#Conclusion

In this episode 3 you've mastered the AlmaLinux installation path from start to production-ready: understanding the three Anaconda installer modes, choosing the right software set, preparing LVM, Btrfs, or encrypted partitions, enabling UEFI Secure Boot, and closing with automated deployment using Kickstart, cloud-init, and the dedicated WSL and Raspberry Pi images.

Key takeaways:

Anaconda supports three modes: graphical, text, and Kickstart.
Choose Minimal or Server for a lean, secure production system.
LVM is the default partitioning scheme; Btrfs offers snapshots; LUKS for encryption.
Kickstart (%packages, %post) automates mass installation.
cloud-init provisions cloud instances from metadata and user-data.
Always upgrade the system right after installation.

A good installation is the foundation of a healthy system. In the next episode, Episode 4, we'll cover package management with DNF5 & repositories — the heart of day-to-day AlmaLinux administration: basic dnf5 commands, dnf5.conf configuration, history and rollback, and managing the BaseOS, AppStream, CRB, and EPEL repositories, up to the official dnf-almalinux plugin. See you there!