Three-Tier Web Application Deployment on AWS EKS using AWS EKS, ArgoCD, Prometheus, Grafana, and Jenkins!

Welcome to the Three-Tier Web Application Deployment project! 🚀

Achieved approximately 1K RPS at sub-250ms P95 latency with 99.9% uptime by designing a scalable microservices architecture deployed on AWS EKS, built for high availability, fault tolerance, and distributed systems reliability.

The system follows a 3-tier microservices-based architecture (React frontend, Node.js backend exposing REST APIs, MongoDB database), with services decoupled and independently scalable, and traffic managed through load balancing and autoscaling policies across a multi-node Kubernetes cluster. Leveraged container orchestration using Kubernetes to manage 25+ containerized workloads across 15–30 pods, ensuring resilience through self-healing, rolling deployments, and horizontal scaling. Provisioned the entire infrastructure using Infrastructure as Code (Terraform), enabling reproducible and production-grade environments.

Built a DevSecOps pipeline with CI/CD (Jenkins) integrating SonarQube (static code analysis) and Trivy (container vulnerability scanning) to enforce secure and high-quality releases. Implemented GitOps using ArgoCD for declarative, automated deployments, and integrated real-time observability (Prometheus + Grafana) to monitor system metrics, resource utilization, and service health, enabling proactive debugging and performance optimization.

🚧 Challenges Faced & Solutions

• Jenkins Pipeline & Terraform Failures
  Initial pipeline executions failed due to misconfigured Terraform scripts and insufficient IAM permissions. Resolved by validating configurations, correcting scripts, and ensuring Jenkins had proper AWS access.

• EKS Node Registration Failure
  Node groups were created and EC2 instances launched, but no nodes appeared in the cluster. Fixed by identifying IAM role mismatch and correctly mapping the node role in the aws-auth ConfigMap.

• IAM Role Misconfiguration for Nodes
  Worker nodes lacked required permissions, causing failures in cluster join and image pulls. Resolved by attaching necessary policies: AmazonEKSWorkerNodePolicy, AmazonEKS_CNI_Policy, and AmazonEC2ContainerRegistryReadOnly.

• aws-auth ConfigMap Editing Issues
  Faced repeated errors due to incorrect YAML formatting and invalid updates. Fixed by properly structuring mapRoles and mapUsers with correct indentation and valid IAM role ARNs.

• ImagePullBackOff & ECR Access Errors
  Pods failed with 403 Forbidden while pulling images from ECR. Resolved by granting ECR read permissions to node IAM role and recreating nodes to apply updated credentials.

• Node Group Degraded State
  Node groups entered a degraded state as instances failed to bootstrap and join the cluster. Diagnosed using logs and resolved by fixing IAM roles, aws-auth mapping, and recreating node groups.

• Node Bootstrap & Cluster Connectivity Issues
  EC2 nodes failed to register due to bootstrap and connectivity issues. Debugged using kubelet logs and ensured proper cluster endpoint access.

• Networking & Internet Access Problems
  Nodes couldn’t reach EKS API/ECR due to subnet/NAT or security group misconfigurations. Fixed by verifying outbound connectivity, route tables, and required network rules.

• Kubernetes Debugging Complexity
  Troubleshooting required deep inspection across IAM, networking, and Kubernetes layers. Developed a systematic debugging approach using kubectl describe, logs, and AWS CLI.

• ArgoCD Deployment Failures
  Applications failed to deploy due to incorrect IAM roles and cluster access issues. Resolved by aligning permissions and ensuring proper cluster connectivity.

📸 Project Screenshots

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🚀 ArgoCD Deployment

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☸️ EKS Cluster & Nodes

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⚙️ Jenkins CI/CD Pipeline

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🏗️ Terraform Infrastructure

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Table of Contents

• Application Code
• Jenkins Pipeline Code
• Jenkins Server Terraform
• Elastic Kubernetes Terraform
• Kubernetes Manifests Files
• Project Details

Application Code

The Application-Code directory contains the source code for the Three-Tier Web Application. Dive into this directory to explore the frontend and backend implementations.

Jenkins Pipeline Code

In the Jenkins-Pipeline-Code directory, you'll find Jenkins pipeline scripts. These scripts automate the CI/CD process, ensuring smooth integration and deployment of your application.

Jenkins Server Terraform

Explore the Jenkins-Server-TF directory to find Terraform scripts for setting up the Jenkins Server on AWS. These scripts simplify the infrastructure provisioning process.

EKS Terraform

The eks directory holds Terraform files our terraform finds to setup VPC and EKS Clusters in its subnets using the specified variables and backend as specified.

Kubernetes Manifests Files

The Kubernetes-Manifests-Files directory holds Kubernetes manifests for deploying your application on AWS EKS. Understand and customize these files to suit your project needs.

Project Details

🛠️ Tools Explored:

• Terraform & AWS CLI for AWS infrastructure
• Jenkins, Sonarqube, Terraform, Kubectl, and more for CI/CD setup
• Helm, Prometheus, and Grafana for Monitoring
• ArgoCD for GitOps practices

🚢 High-Level Overview:

• IAM User setup & Terraform magic on AWS
• Jenkins deployment with AWS integration
• EKS Cluster creation & Load Balancer configuration
• Private ECR repositories for secure image management
• Helm charts for efficient monitoring setup
• GitOps with ArgoCD - the cherry on top!

📈 The journey covered everything from setting up tools to deploying a Three-Tier app, ensuring data persistence, and implementing CI/CD pipelines.

Happy Coding! 🚀