Cluster Config GitOps Repository Template

This is a template GitOps repository structure for managing ROSA HCP cluster configurations using ArgoCD and the App-of-Apps pattern.

Repository Structure

cluster-config/
├── README.md                    # This file
├── .gitignore                  # Git ignore rules
├── {environment}/              # Environment directory (e.g., dev, staging, prod, nonprod)
│   └── {cluster-name}/         # Cluster-specific directory
│       ├── infrastructure.yaml  # Infrastructure components configuration
│       ├── applications-ns.yaml # Application namespace configuration
│       └── namespaces/          # Optional: Team/application namespace configs
│           └── {team}-{apmnum}.yaml
└── templates/                  # Optional: Template files for new clusters
    ├── infrastructure.yaml.template
    └── applications-ns.yaml.template

Usage

1. Initialize as Git Repository

cd reference/cluster-config
git init
git add .
git commit -m "Initial commit: Cluster config template"
git remote add origin https://github.com/your-org/cluster-config.git
git push -u origin main

2. Create Cluster Configuration

For each cluster, create a directory structure:

mkdir -p {environment}/{cluster-name}
cp templates/infrastructure.yaml.template {environment}/{cluster-name}/infrastructure.yaml
cp templates/applications-ns.yaml.template {environment}/{cluster-name}/applications-ns.yaml

3. Configure Cluster-Specific Values

Edit the YAML files with cluster-specific values:

• Update AWS_REGION in infrastructure.yaml
• Update clusterName in both files
• Add infrastructure components as needed
• Add application teams as needed

4. Git Path Format

The gitPath used in Terraform/bootstrap script should match the directory structure:

• Directory: nonprod/np-hub/
• gitPath: nonprod/np-hub

Configuration Files

infrastructure.yaml

Defines infrastructure components deployed via GitOps:

• Storage (EFS, EBS)
• Logging (CloudWatch)
• Compliance operators
• Security operators
• Platform tools

applications-ns.yaml

Defines application teams and their namespaces:

• Team configurations
• ArgoCD project setup
• Namespace definitions

namespaces/{team}-{apmnum}.yaml

Team-specific namespace configurations:

• Namespace definitions
• Resource quotas
• RBAC configurations
• Service accounts

Integration with Terraform

This repository is referenced by the Terraform bootstrap script via the GIT_PATH environment variable:

export GIT_PATH="nonprod/np-hub"

The bootstrap script will:

1. Install the cluster-bootstrap Helm chart
2. Create ArgoCD ApplicationSets that reference this repository
3. ArgoCD will sync applications based on the YAML files in this repo

Best Practices

1. Version Control: Keep all cluster configurations in Git
2. Environment Separation: Use separate directories for different environments
3. Cluster Isolation: Each cluster has its own directory
4. Incremental Updates: Start with empty infrastructure/applications lists and add components gradually
5. Documentation: Document any custom configurations or decisions

References

• App-of-Apps Infrastructure Chart
• App-of-Apps Application Chart
• Cluster Bootstrap Chart