Deploying workloads on EKS in AWS - Step-by-Step Execution

Process Flow - Deploying workloads on EKS

Create EKS Cluster

↓

Configure kubectl

↓

Write Deployment YAML

↓

Apply Deployment

↓

Pods start running

↓

Verify workload status

↓

Done

This flow shows the steps to deploy an application on EKS: create cluster, configure access, write deployment, apply it, pods run, verify.

Execution Sample

AWS

eksctl create cluster --name my-cluster --region us-west-2
aws eks --region us-west-2 update-kubeconfig --name my-cluster
kubectl apply -f deployment.yaml
kubectl get pods

Creates an EKS cluster, configures kubectl, deploys a workload using a YAML file, then checks pod status.

Process Table

Step	Action	Command/Description	Result/State
1	Create EKS Cluster	eksctl create cluster --name my-cluster --region us-west-2	Cluster 'my-cluster' created and ready
2	Configure kubectl	aws eks --region us-west-2 update-kubeconfig --name my-cluster	kubectl configured to access cluster
3	Write Deployment YAML	deployment.yaml with container image and replicas	Deployment manifest ready
4	Apply Deployment	kubectl apply -f deployment.yaml	Deployment created, pods starting
5	Pods start running	kubectl get pods	Pods in Running state
6	Verify workload	kubectl describe deployment my-app	Deployment ready with desired replicas
7	Exit	All pods running and workload deployed	Deployment successful, process complete

💡 All pods are running and deployment is successful, so deployment process ends.

Status Tracker

Variable	Start	After Step 1	After Step 4	After Step 5	Final
Cluster State	None	Created	Created	Created	Created
kubectl Config	None	Configured	Configured	Configured	Configured
Deployment Status	None	None	Created	Pods Running	Pods Running
Pods State	None	None	None	Running	Running

Key Moments - 3 Insights

Why do we need to configure kubectl after creating the cluster?

kubectl needs cluster access info to communicate with EKS. Step 2 shows configuring kubectl after cluster creation.

What happens if pods do not reach Running state after applying deployment?

Pods may be pending or failing. Step 5 shows pods starting; if not Running, check pod logs or events.

Why is writing a deployment YAML important before applying?

Deployment YAML defines what to deploy and how. Step 3 prepares this manifest, which kubectl uses in Step 4.

Visual Quiz - 3 Questions

Look at the execution table, what is the cluster state after Step 1?

A Configured

B None

C Created

D Running

💡 Hint

Check the 'Cluster State' variable in variable_tracker after Step 1.

At which step do pods start running?

A Step 3

B Step 5

C Step 4

D Step 2

💡 Hint

Look at the 'Pods State' variable in variable_tracker and the execution_table rows.

If kubectl is not configured, what will happen when applying deployment?

A kubectl cannot connect to cluster, deployment fails

B Deployment applies successfully

C Pods start running anyway

D Cluster is automatically configured

💡 Hint

Refer to Step 2 and Step 4 in execution_table and kubectl Config variable in variable_tracker.

Concept Snapshot

Deploying workloads on EKS:
1. Create EKS cluster (eksctl).
2. Configure kubectl to access cluster.
3. Write deployment YAML with app details.
4. Apply deployment with kubectl.
5. Pods start running and workload is live.
Always verify pod status after deployment.

Full Transcript

To deploy workloads on EKS, first create a cluster using eksctl. Then configure kubectl to connect to the cluster. Next, write a deployment YAML file describing your application and how many replicas you want. Apply this deployment using kubectl apply. The pods will start running in the cluster. Finally, verify the pods are running and the deployment is ready. This process ensures your application runs on the managed Kubernetes cluster.

Practice

1. What is the main purpose of Amazon EKS when deploying workloads?

easy

A. To run containerized applications using Kubernetes without managing servers

B. To store large amounts of data in the cloud

C. To create virtual machines for running applications

D. To manage user access and permissions

Solution

1. Step 1: Understand EKS functionality

   Amazon EKS is a managed Kubernetes service that lets you run containers without managing the underlying servers.

2. Step 2: Compare options

   Storing data relates to services like S3, creating VMs to EC2, and managing permissions to IAM--none of which is EKS's core purpose.

3. Final Answer:

   To run containerized applications using Kubernetes without managing servers -> Option A

4. Quick Check:

   EKS = Managed Kubernetes for containers [OK]

Hint: EKS = Kubernetes service for containers, not storage or VMs [OK]

Common Mistakes:

• Confusing EKS with storage services like S3
• Thinking EKS manages virtual machines directly
• Mixing EKS with IAM user management

2. Which of the following is the correct command to deploy an application using a YAML file named app-deployment.yaml on EKS?

easy

A. kubectl run app-deployment.yaml

B. eksctl create app app-deployment.yaml

C. aws eks deploy app-deployment.yaml

D. kubectl apply -f app-deployment.yaml

Solution

1. Step 1: Identify the kubectl command for applying YAML

   The correct command to deploy resources defined in a YAML file is kubectl apply -f filename.

2. Step 2: Evaluate other options

   kubectl run app-deployment.yaml is for running individual pods, not applying YAML manifests. eksctl create app app-deployment.yaml misuses eksctl, which is primarily for EKS cluster creation. aws eks deploy app-deployment.yaml is not a valid AWS CLI command.

3. Final Answer:

   kubectl apply -f app-deployment.yaml -> Option D

4. Quick Check:

   Deploy YAML with kubectl apply -f [OK]

Hint: Use kubectl apply -f for YAML deployment files [OK]

Common Mistakes:

• Using eksctl for direct YAML deployment
• Confusing kubectl run with apply
• Trying AWS CLI commands that don't exist

3. Given this YAML snippet for a Deployment on EKS:

apiVersion: apps/v1
kind: Deployment
metadata:
  name: myapp
spec:
  replicas: 3
  selector:
    matchLabels:
      app: myapp
  template:
    metadata:
      labels:
        app: myapp
    spec:
      containers:
      - name: myapp-container
        image: nginx:latest

What will be the number of running pods after applying this deployment?

medium

A. 1

B. 3

C. 0

D. Depends on the node capacity

Solution

1. Step 1: Read the replicas field in the Deployment spec

   The YAML specifies replicas: 3, which means Kubernetes will create 3 pods for this deployment.

2. Step 2: Understand pod creation behavior

   Unless there is a scheduling issue, Kubernetes will run 3 pods as requested.

3. Final Answer:

   3 -> Option B

4. Quick Check:

   replicas = number of pods running [OK]

Hint: replicas field sets pod count in Deployment spec [OK]

Common Mistakes:

• Assuming only 1 pod runs by default
• Thinking pods depend on node capacity without error
• Confusing selector labels with pod count

4. You tried to deploy a workload on EKS using kubectl apply -f deployment.yaml, but got an error: error: unable to recognize "deployment.yaml": no matches for kind "Deploy". What is the likely cause?

medium

A. The cluster is not running

B. kubectl is not installed

C. The YAML file has a typo in the kind field; it should be 'Deployment' not 'Deploy'

D. The image name in the YAML is incorrect

Solution

1. Step 1: Analyze the error message

   The error says no matches for kind "Deploy", which means Kubernetes does not recognize this resource kind.

2. Step 2: Check the YAML kind field

   The correct kind for workload deployment is "Deployment", not "Deploy". This typo causes the error.

3. Final Answer:

   The YAML file has a typo in the kind field; it should be 'Deployment' not 'Deploy' -> Option C

4. Quick Check:

   Kind field must be exact Kubernetes resource name [OK]

Hint: Check resource kind spelling in YAML for errors [OK]

Common Mistakes:

• Ignoring error details about resource kind
• Assuming cluster or kubectl issues without checking YAML
• Blaming image name for syntax errors

5. You want to deploy a stateless web app on EKS that automatically scales between 2 and 5 pods based on CPU usage. Which combination of Kubernetes resources should you define in your YAML files?

hard

A. A Deployment with replicas set to 2 and a Horizontal Pod Autoscaler targeting CPU usage with max replicas 5

B. A StatefulSet with replicas 5 and a LoadBalancer service

C. A DaemonSet to run pods on every node and a Cluster Autoscaler

D. A Deployment with replicas fixed at 5 and a NodePort service

Solution

1. Step 1: Identify resource for managing pod replicas with scaling

   A Deployment manages stateless pods and can be combined with a Horizontal Pod Autoscaler (HPA) to scale pods based on CPU.

2. Step 2: Understand autoscaling setup

   Set Deployment replicas to minimum 2, and HPA to scale up to max 5 pods based on CPU usage.

3. Step 3: Evaluate other options

   StatefulSet is for stateful apps, DaemonSet runs pods on all nodes (not scaling pods), fixed replicas do not autoscale.

4. Final Answer:

   A Deployment with replicas set to 2 and a Horizontal Pod Autoscaler targeting CPU usage with max replicas 5 -> Option A

5. Quick Check:

   Deployment + HPA = autoscaling pods [OK]

Hint: Use Deployment + HPA for CPU-based pod autoscaling [OK]

Common Mistakes:

• Using StatefulSet for stateless apps
• Confusing DaemonSet with autoscaling pods
• Setting fixed replicas without autoscaler