“Kubernetes Fundamentals Explained — What, Why, and When for Every Core Component”

 Pods → run
Service → expose
Ingress → route
Storage → save data
Config → settings
Helm → manage apps
Monitoring → observe
EKS → production

Let’s slow it down and explain WHY each piece exists + WHAT problem it solves + WHEN we use it — like real-world thinking, not textbook style.

Think of Kubernetes like building a house 🏠
Each object has a job.

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🧱 1️⃣ Pods → run

🧠 What?

Smallest unit that runs containers.

Why?

Containers cannot run directly in Kubernetes.
They must live inside a Pod.

👉 Pod = wrapper for container

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Real-world use

Run your app:

• nginx

• nodejs

• python app

• API

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Problem it solves

Without Pod → no workload runs

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Example

kubectl run nginx --image=nginx

👉 Now app is running

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Easy memory

Pod = process

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🌐 2️⃣ Services → expose

🧠 What?

Gives network access to Pods.

Why?

Pods have:
❌ random IPs
❌ change when recreated

So you can’t connect reliably.

Service gives:
✅ stable IP
✅ stable DNS name

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Real-world use

Expose:

• frontend

• backend

• API

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Problem it solves

Without Service:

browser ❌ cannot reach app

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Example

kubectl expose deployment nginx --port=80 --type=NodePort

👉 Now reachable from outside

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Easy memory

Service = door to your app

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🚦 3️⃣ Ingress → route

🧠 What?

Smart HTTP router

Why?

If you have:

frontend
backend
auth

You don’t want:

3 NodePorts ❌

Instead:

/ → frontend
/api → backend
/login → auth

Single entry point

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Real-world use

Production websites

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Problem it solves

Too many ports + messy routing

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Easy memory

Ingress = traffic police 🚦

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💾 4️⃣ Storage → save data

🧠 What?

Persistent storage for Pods

Why?

Pods are temporary.

If Pod restarts:
❌ data lost

So DB/files disappear

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Real-world use

• MySQL

• Postgres

• uploads

• logs

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Problem it solves

Data loss

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Easy memory

Pod dies → data survives

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⚙️ 5️⃣ Config → settings

🧠 What?

Store configs separately from code

• ConfigMap → normal config

• Secret → passwords/keys

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Why?

Hardcoding:
❌ insecure
❌ hard to change

Better:

change config → no rebuild

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Real-world use

• DB URL

• API keys

• environment variables

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Easy memory

Config = app settings file

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📦 6️⃣ Helm → manage apps

🟢 Helm

🧠 What?

Package manager for Kubernetes

Like:

apt install nginx

Helm:

helm install prometheus

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Why?

Writing 20 YAML files manually = pain

Helm:
✅ reusable
✅ versioned
✅ easy install/upgrade

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Real-world use

Install:

• Prometheus

• Grafana

• Redis

• Kafka

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Easy memory

Helm = npm/apt for k8s

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📊 7️⃣ Monitoring → observe

Tools

• Prometheus

• Grafana

🧠 Why?

If app crashes, how will you know?

Need:

• CPU usage

• memory

• alerts

• graphs

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Real-world use

SRE teams watch dashboards daily

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Problem it solves

Blind production

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Easy memory

Monitoring = health report

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☁️ 8️⃣ EKS → production

🟢 Amazon EKS

🧠 What?

Managed Kubernetes on AWS

Why?

Minikube is only local

Production needs:

• multiple nodes

• HA

• autoscaling

• load balancer

• security

EKS provides all

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Real-world use

Companies deploy apps here

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Easy memory

Minikube = practice
EKS = real world

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🔥 Final Big Picture (super clear)

Pod       → run app
Service   → access app
Ingress   → route traffic
Storage   → save data
Config    → manage settings
Helm      → install apps easily
Monitoring→ observe health
EKS       → production cluster

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If you master just these 8 concepts properly
👉 you’re already ahead of 80% Kubernetes learners 😄🔥