Skip to content

Day 1 · DevOps Introduction & Environment Setup

Slides

📊 Open the intro slide deck — course & DevOps introduction: history, culture, and what a DevOps engineer does.

Learning Objectives

  • Understand what DevOps is and why it exists
  • Set up a consistent Linux environment using Vagrant
  • Navigate the Linux filesystem with basic commands

Theory · ~20 min

What is DevOps?

DevOps is not a tool or a job title — it is a culture and a set of practices that bridges software development (writing code) and operations (running that code in production).

Before DevOps, these two teams worked in silos:

  • Developers wrote code and threw it "over the wall" to operations
  • Operations ran the servers and were blamed when things broke
  • Releases were infrequent, risky, and painful

DevOps changes this by emphasizing:

Principle Meaning
Collaboration Dev and Ops work together throughout the lifecycle
Automation Anything done manually more than twice should be scripted
Continuous delivery Small, frequent releases instead of big risky ones
Observability You can't fix what you can't see — monitor everything
Feedback loops Fast feedback from tests, monitoring, and users

The DevOps Lifecycle

Plan → Code → Build → Test → Release → Deploy → Operate → Monitor
  ↑___________________________________________________|

This course covers the right half — infrastructure, deployment, and monitoring. Understanding the full loop matters for the job.

What Does a DevOps Engineer Actually Do?

A useful way to think about the role: whatever the specific tool, almost every DevOps responsibility falls under one of six key scopes. A DevOps engineer manages:

Scope What it covers
Infrastructure Provisioning and running servers, VMs, containers, and cloud resources (often as code)
Networking Connectivity, DNS, load balancers, firewalls, VPCs, TLS
Security Access control, secrets, hardening, patching, least privilege
Automation CI/CD pipelines and scripting to remove repetitive manual work
Monitoring Metrics, logs, alerts, and responding when things break
Cost Control Right-sizing resources and keeping cloud spend under control

You won't master all six in 30 days — but you'll understand each well enough to contribute from Day 1 on the job.

Why Vagrant?

Throughout this course, you'll run labs inside a Linux VM managed by Vagrant. This gives everyone the same Ubuntu 24.04 environment regardless of whether you're on macOS, Windows, or Linux.

Vagrant manages VMs with a single config file (Vagrantfile) and a handful of commands. It sits on top of a hypervisor (VirtualBox or VMware Fusion) that actually runs the VM.

Your machine (any OS)
    └── Hypervisor (VirtualBox or VMware Fusion)
            └── Ubuntu 24.04 LTS VM  ← where all our labs run
                    └── managed by Vagrant

Machine Setup

Step 1 — Know your machine architecture

Before installing anything, check whether your machine is amd64 (Intel/AMD) or arm64 (Apple Silicon M1/M2/M3):

uname -m
# x86_64  → amd64 (Intel Mac)
# arm64   → arm64 (Apple Silicon)

Settings → System → About → System type

uname -m
# x86_64  → amd64
# aarch64 → arm64

Step 2 — Install VirtualBox

We use VirtualBox as the hypervisor for this course — it's free, works on all platforms, and has native Vagrant support.

Download and install from virtualbox.org/wiki/Downloads

Apple Silicon users

ARM64 support requires VirtualBox 7.1 or later. Make sure you download the latest version.

Step 3 — Install Vagrant

Download and install from developer.hashicorp.com/vagrant/install

vagrant --version    # should print 2.x.x

Step 4 — Spin up your VM

4.1 Create relevant directories

mkdir -p ~/devops-month-labs/day-1
cd ~/devops-month-labs/day-1

4.1 Create a Vagrantfile

Create a file named Vagrantfile (no extension) and paste this content. It works on both amd64 and arm64 — bento/ubuntu-24.04 supports both architectures automatically.

Vagrant.configure("2") do |config|
  config.vm.box      = "bento/ubuntu-24.04"
  config.vm.hostname = "devops-lab"

  config.vm.network "private_network", ip: "192.168.56.10"

  config.vm.provider "virtualbox" do |vb|
    vb.name   = "devops-lab"
    vb.memory = 1024
    vb.cpus   = 1
  end
end

# Start the VM (first run downloads the box ~500MB)
vagrant up

# Check the status of vagrant box
vagrant status

# SSH into it
vagrant ssh

Your prompt changes to:

vagrant@devops-lab:~$

Everything from here runs inside the VM.

NOTE: For finding all the available vagrant boxes => https://portal.cloud.hashicorp.com/vagrant/discover

Step 5 — Explore the OS

# What OS and version?
cat /etc/os-release

# Kernel version and architecture
uname -a
uname -m      # should print x86_64 or aarch64

# Who are you?
whoami
id

# Hostname
hostname

# Uptime and load
uptime

Step 6 — Navigate the filesystem

The Linux filesystem starts at / — everything branches from there:

/
├── etc/    → configuration files (nginx.conf, sshd_config)
├── home/   → user home directories (/home/vagrant)
├── var/    → logs, databases, variable data (/var/log)
├── tmp/    → temporary files, cleared on reboot
├── usr/    → installed programs and libraries
└── proc/   → live kernel and process info (virtual, not real files)

pwd             # where am I right now?
ls              # list current directory
ls -la          # long format, include hidden files (dotfiles)

cd /            # go to root
ls              # see all top-level directories

cd /etc         # go into the config directory
ls | head -20   # first 20 entries

cd /var/log     # go to logs
ls -lh          # list with human-readable sizes

cd ~            # back to home (/home/vagrant)
pwd             # confirm

Step 7 — Create and manage files

mkdir -p ~/practice/week-01
cd ~/practice/week-01

# Create a file
echo "Day 01 - DevOps Month" > notes.txt
cat notes.txt

# Copy and move
cp notes.txt notes-backup.txt
mv notes-backup.txt notes-v2.txt
ls -la

# Delete
rm notes-v2.txt
ls

# Create nested directories
mkdir -p projects/myapp/config
ls -R projects/

Step 8 — Exit and manage the VM

exit    # back to your host machine

# From your host:
vagrant status    # VM state
vagrant halt      # shut down gracefully
vagrant up        # start again
vagrant ssh       # SSH back in

Warning

vagrant destroy deletes the VM and all files inside it. vagrant halt just shuts it down — your files survive.

Assignment

  1. Practice Basic Commands, System Information, File and Directory Management section cheat sheets from this repository

  2. Register your own .com.np domain. You'll use it later in the course when we deploy and serve real applications. Registration is free — follow the official guide: How to register a .np domain.

  3. Set up an AWS account so you're ready for the cloud sessions. Pick whichever applies to you:

    Guard your credit card and free-tier limits

    A credit card is required even for the Free Tier. Stay within free-tier limits, and stop or delete any resources you're not using so you don't get charged. Never share your card details or AWS credentials with anyone.