Linux Server Installation

By Pooja | 21st July 2025

Introduction

In the rapidly evolving DevOps landscape, Linux servers form the backbone of automation, CI/CD pipelines, container orchestration, cloud platforms, and infrastructure as code. From provisioning and configuring environments to hosting microservices and running monitoring tools, Linux is central to DevOps operations.

Before setting up tools like Docker, Kubernetes, Jenkins, or Ansible, DevOps engineers must understand how to install and configure Linux servers efficiently. This article walks through the step-by-step installation process, including planning, execution, post-install setup, and automation.

Why Linux in DevOps

Linux is the default platform for DevOps because:

Open-source and free
Lightweight and customizable
Rich CLI and scripting capabilities
Compatibility with cloud platforms (AWS, Azure, GCP)
Supports container tools like Docker and Kubernetes
Community and enterprise support (e.g., RHEL, Ubuntu, CentOS, Debian)

DevOps tools are built on or optimized for Linux, making it the go-to operating system for infrastructure provisioning and automation.

Planning a Linux Server Installation

Before beginning installation, define:

Use case: Web server, build server, database, CI/CD, etc.
Resources required: CPU, RAM, disk size
Environment type: Development, staging, production
Virtual or bare-metal: On-premises vs. cloud
Network requirements: Static/DHCP IP, firewall, DNS
Security compliance: SSH access, user roles, packages

Planning ahead helps avoid post-installation errors and reduces downtime.

Choosing the Right Linux Distribution

Select a distribution that matches your DevOps goals:

Distribution	Use Case	Notes
Ubuntu Server	CI/CD, Web Servers	Easy to use, popular in cloud
CentOS / Rocky Linux / AlmaLinux	RHEL-compatible setups	Used in enterprise systems
Debian	Stable environments	Excellent package management
Red Hat Enterprise Linux (RHEL)	Production/Enterprise	Support and security updates
Amazon Linux	AWS optimized	Fast boot, tuned for EC2
SUSE Linux Enterprise Server	SAP, database servers	Enterprise-grade, YaST tools

For DevOps labs or Docker hosts, Ubuntu Server is often preferred for its simplicity and compatibility.

Installation Methods

Manual Installation

Used for small setups or local testing
Boot from ISO or USB and install via GUI or CLI

Automated Installation

For large-scale or repeatable deployments
Uses kickstart (RHEL), preseed (Debian/Ubuntu), PXE boot, or cloud-init

Cloud Provisioning

Use pre-configured images via AWS EC2, Azure VM, or GCP Compute Engine
Automate with Terraform or Ansible

Cloud Provisioning

Step 1: Prepare the Installation Medium

Download the desired ISO from the official site:

Ubuntu: https://ubuntu.com/download/server
CentOS/RHEL: https://www.centos.org/download/ or via Red Hat portal

Create a bootable USB:

bash

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sudo dd if=ubuntu-20.04.iso of=/dev/sdX bs=4M status=progress

For virtual machines, mount ISO in virtualization tools like VirtualBox, VMware, or Proxmox.

Step 2: Configure BIOS/UEFI

Boot into BIOS (usually with F2, Del, or Esc)
Enable virtualization support (if needed)
Set boot order to prioritize USB or ISO
Optionally disable secure boot for Linux compatibility

Step 3: Boot into Installer

After booting:

Select language and keyboard layout
Choose “Install Ubuntu Server” or similar option
Begin guided or manual setup

Step 4: Partitioning the Disk

You can use:

Automatic partitioning (safe for new disks)
Manual partitioning for custom layouts

Typical partitions:

/boot: 1 GB
/: root partition (20–100 GB or more)
swap: 1–2x RAM (optional)
/home: optional (for separating user data)
/var: separate for logs and Docker

Use LVM or ZFS for snapshotting and flexibility.

Step 5: Set Hostname and Users

Define hostname (e.g., ci-server, web-node-1)
Create a non-root user with sudo privileges
Optionally enable SSH during installation
Import SSH keys for secure access

Step 6: Install Software and Services

Most distributions allow you to select:

OpenSSH server
Docker, LAMP stack, PostgreSQL, etc.
Automatic updates or unattended upgrades

You can also delay software installation and use a tool like Ansible later.

Step 7: Finalize Installation

Review configuration
Begin installation
Reboot after install completes
Login using the created user account

Congratulations! Your Linux server is ready.

Post-Installation Setup

After first login, configure:

Update the system

bash

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sudo apt update && sudo apt upgrade -y # Ubuntu

sudo dnf update -y # RHEL/CentOS

Configure firewall

bash

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sudo ufw enable

sudo ufw allow ssh

sudo ufw allow 80/tcp

Add essential packages

bash

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sudo apt install git curl vim net-tools htop unzip

Configure time zone

bash

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sudo timedatectl set-timezone Asia/Kolkata

Enable SSH key login

Upload public key to ~/.ssh/authorized_keys

Enable SSH key login

Automation is a key DevOps principle. Linux servers can be provisioned using:

Cloud-init: Automatically run scripts on first boot in cloud
Kickstart/Preseed: Automate full OS installations
Ansible: Automate configuration after OS setup
Terraform: Provision VMs with predefined images
Packer: Build golden OS images with tools preinstalled

Example (cloud-init user-data):

yaml

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#cloud-config

packages:

– docker.io

users:

– name: devops

groups: sudo

shell: /bin/bash

ssh-authorized-keys:

– ssh-rsa AAAA…

Server Hardening and Security

Securing the Linux server is critical in production:

Disable root login via SSH
Use SSH key authentication
Install and configure fail2ban
Set up regular updates and alerts
Limit open ports and services
Monitor with tools like Prometheus, Grafana, or ELK

Integration with DevOps Tools

Once installed, Linux servers can host:

Tool	Purpose
Jenkins	CI/CD pipelines
Docker	Container runtime
Kubernetes	Container orchestration
GitLab	Source control + CI/CD
Prometheus	Monitoring
Nginx/Apache	Web services

You can also configure systemd services, cron jobs, or use GitOps practices with tools like ArgoCD.

Real-World Scenarios

CI Server Setup: Install Jenkins on Ubuntu, open ports 8080/22, install Java.
Docker Host: Provision CentOS server with Docker, expose port 2375 (with care).
Monitoring Node: Install node exporter, configure Prometheus target.

These servers can be cloned or imaged for scaling up infrastructure.

Best Practices

Always update packages post-install.
Disable unused services.
Use SSH keys, not passwords.
Automate everything (scripts, tools, infrastructure).
Use LTS (Long-Term Support) versions of OS.
Test in virtual machines before production deployment.
Backup configuration and system images.

Conclusion

Installing and configuring Linux servers is a foundational skill for DevOps engineers. Whether you’re spinning up a CI runner, building a Docker host, or deploying infrastructure in the cloud, understanding the installation process, automation techniques, and post-install configuration is essential.

With Linux at the core of most DevOps pipelines and tools, mastery over server installation helps you build reliable, secure, and reproducible systems, aligned with DevOps principles of automation, scalability, and continuous improvement.