WordPress on EKS + RDS + EFS

Deployment of WordPress on Amazon EKS using EFS for file persistence and RDS (MySQL) as the database backend.

Full architecture explanation: docs/architecture.md

Repository Structure

wordpress-eks/
├── README.md
├── docs/
│   ├── architecture.md      # Architecture description and design decisions
│   ├── step-by-step.md      # Full deployment guide
│   └── cost-estimate.md     # AWS cost breakdown
├── iac/
│   ├── 01-storageclass.yaml # EFS StorageClass
│   ├── 02-pv.yaml           # PersistentVolumes
│   ├── 03-pvc.yaml          # PersistentVolumeClaims
│   ├── 04-mariadb.yaml      # MariaDB deployment (phase 1 only)
│   ├── 05-wp-deployment.yaml# WordPress Service + Deployment
│   └── 06-rds-svc.yaml      # ExternalName Service pointing to RDS
└── images/                  # Screenshots and Icons

Deployment

The deployment is done in two phases:

Phase 1 — MariaDB on Kubernetes: WordPress + MariaDB both running as pods, sharing an EFS volume. Simple but not production-ready (EFS is not optimal for databases).

Phase 2 — RDS migration: MariaDB pod replaced by an RDS MySQL instance. WordPress pod remains unchanged; only a Service/ExternalName is swapped. This enables horizontal scaling.

See docs/step-by-step.md for the full deployment guide.

Prerequisites

• EKS cluster running with worker nodes
• EC2 instance with kubectl configured
• EFS CSI Driver add-on installed on the cluster
• AWS CLI configured with valid session credentials

Key Concepts

• EFS Access Points with POSIX UIDs matching container users (999 for MariaDB, 33 for WordPress) allow pods to create their directories on first run without manual intervention.
• Kubernetes Secret stores the DB password and is injected as an env var into both MariaDB and WordPress containers.
• Service/ExternalName allows pods to reach RDS using the same internal DNS name as the old MariaDB service — no changes to the WordPress manifest needed when migrating.
• ReadWriteMany (RWX) access mode on EFS PVCs allows multiple WordPress replicas to share the same /var/www/html directory simultaneously.