Overview

This project involves containerizing a traditional, multi-tier Java web application using Docker and Docker Compose. The primary objective is to replicate a production-grade architecture that transitions from virtual machine-based monolith deployments to a lightweight, scalable, and portable containerized model.

By isolating services and using Docker best practices (e.g. multi-stage builds, service orchestration, image optimization), we improve resource utilization, simplify deployments, and align with microservices principles.

Legacy Architecture: Challenges

Before containerization, the application ran across virtual machines using a typical n-tier architecture. Though functional, this model suffered from several significant limitations:

Key Issues:

1. High CapEx and OpEx: VMs are resource-intensive and costly to scale.
2. Manual Deployments: Frequent deployments led to increased chances of human error.
3. Rigid Architecture: Difficult to align with microservices or CI/CD workflows.
4. Resource Waste: VMs often over-provision CPU/memory.
5. Lack of Environment Parity: Discrepancies between dev/staging/prod environments.

Solution: Container-Based Modernization

Why Containers?

• Lightweight compared to VMs (no guest OS).
• Portable across OS/devices due to standard image packaging.
• Isolated, enabling microservices.
• Repeatable, offering version-controlled builds and environments.