AWS Base Infrastructure (Terraform)

Modular Terraform layout for core AWS networking.

Design Architecture Diagram

What this demonstrates

• IaC with reusable modules and remote state (S3 backend and lockfile).
• Networking: VPC, multi-AZ subnets, static private IP via ENI.
• Compute: EC2 attached to a pre-created network interface.
• Kubernetes: EKS cluster with a dedicated IAM role and authentication_mode = "API".

Tech stack

Area	Choice
IaC	Terraform, AWS provider
State	S3 backend + lockfile
Region	Configurable (default ap-southeast-1)
Orchestration	Amazon EKS

Repository layout

Path	Role
main.tf	Root module: wires VPC, subnets, NIC, EC2, IAM, EKS
variables.tf	Root variables (e.g. region)
modules/vpc	VPC
modules/subnet	Subnet (reused for EC2 and cluster AZs)
modules/nic	Elastic network interface
modules/ec2	EC2 instance bound to ENI
modules/iam_role	IAM role (EKS assume role policy)
modules/eks	EKS cluster resource

Prerequisites

• Terraform 1.x (compatible with your lockfile).
• AWS CLI configured with credentials that can create the resources above.
• An S3 bucket (and appropriate IAM) for the backend defined in main.tf.

Implementation timeline (portfolio build log)

Date	Delivered
2026-05-05	VPC module, subnet module
2026-05-06	EC2 subnet wiring, NIC module, EC2 module
2026-05-12	IAM role module, EKS module
2026-05-13	update readme.md

Troubleshooting (local dev)

• AWS CLI profiles — Conflicting or stale default credentials in %USERPROFILE%\.aws\credentials (Windows) or ~/.aws/credentials can make the wrong account active. Prefer named profiles and AWS_PROFILE, or remove overlapping [default] entries while testing.
• ENI / connectivity — If an instance or ENI behaves unexpectedly, confirm subnet routing, security groups (if added later), and that the ENI is in the intended subnet and AZ.