Transition to Microservices with Amazon EKS for an IT Consulting Company

Key Results

By moving to a microservices architecture on Amazon EKS, we achieved:

• Agility & Speed: Simplified deployments using microservices, enabling quick implementation of new features. 
• 40% Cost Reduction Optimized containerized workloads reduced EC2 usage.
• Improved Security Posture: Enhanced threat detection, enabling the security scanning of individual microservices. 
• Enhanced Observability: Improved cloud-native monitoring and logging capabilities 
• Operational Simplicity: Transition to GitOps-based deployments greatly reduces operational overhead. 

About the Client

A Tokyo-based IT services and consulting firm providing software development, business solutions, and corporate training to support digital transformation and operational efficiency.

The Challenge 

The client’s monolithic application ran on Amazon EC2 with Auto Scaling Groups. While functional, it caused several challenges:

• Rigid architecture limited flexibility for scaling specific services.
  
• Higher operational costs due to resource inefficiencies.
  
• Complexity in managing deployments and updates.
  
• Growing overhead slowed the pace of development.

Our Solution

We designed and deployed a modern Kubernetes environment on Amazon EKS, laying the foundation for a microservices-based architecture. The solution addressed scalability, security, and operational efficiency through the following key steps:

• Infrastructure as Code with Terraform
  A new EKS cluster and all supporting resources were deployed using Terraform. This ensured that the entire environment was reproducible, consistent, and easy to maintain across development stages.
  
• GitOps with ArgoCD
  ArgoCD was introduced to enable GitOps-based workflows, giving the development team a streamlined and automated deployment process. This reduced manual effort and provided better visibility and control over application releases.
  
• Istio Service Mesh
  Istio was integrated to strengthen security and observability within the Kubernetes environment. It provided complete control over ingress and egress traffic, improved service-to-service communication, and enhanced monitoring capabilities.
  
• Secure Access and Governance
  Single Sign-On (SSO) was implemented across all cluster services, ensuring both secure and simplified access for the team. IAM was configured using IAM Roles for Service Accounts and Pod Identities, giving our client fine-grained access control for workloads running on EKS.
  
• Enhanced Security Practices
  Runtime security tooling was deployed to detect abnormal behavior, potential threats, and compliance violations. In addition, a modernized approach to secrets management was introduced, combining AWS Secrets Manager with Kubernetes secrets for secure and flexible configuration storage.
  
• Cloud-Native Monitoring and Logging
  To improve visibility and troubleshooting, cloud-native monitoring tools were implemented alongside Amazon OpenSearch Service. This provided deeper insights into container logs and system performance, helping the operations team maintain reliability at scale.

Impact of our Work

Now the client can independently scale critical microservices, improving performance while reducing costs. Deployments are faster and safer thanks to small, isolated services and GitOps capabilities. Built-in security, governance, and Istio traffic control ensure safe, auditable operations, while unified monitoring and service-level autoscaling provide clear visibility, operational efficiency, and long-term flexibility for upgrades and experimentation.