DevAx Connect - Managing EKS Cluster Fullstack with CDK (09/01/2020)

Presenter: AWS Solutions Architect Jiwon Yeom
Material: AWS workshop

What It Means to Manage Kubernetes Clusters Fullstack with IaC

Defining infrastructure as code (Infrastructure as Code, IaC) in the cloud is not a choice but a necessity
When deploying Kubernetes clusters to the cloud, there are three main types of code to consider:

image-20200902163604957

When deploying a single EKS cluster on AWS Cloud,
- VPC configuration
- Subnets within it
- Security groups
- Various IAM roles and policies, etc., require multiple configurations
As usage expands through region expansion, account expansion, etc., infrastructure definition code becomes more complex

After defining infrastructure as code, there are resources that must be managed at the cluster level
- ex)
  - Separating namespaces and specifying ResourceQuota for them, or configuring auto-scaling, monitoring, logging settings, etc.

Depending on the organization, who handles it may vary, but at the application layer as well:
1. Deployment scripts
2. K8s manifest
  These should also be managed as code together

By managing all modeling resources as a single source, you can standardize components used across the entire organization
- This enables compliance with enterprise policies and faster response when issues occur
Automation and deployment application resources are provisioned in a safe and repeatable manner, allowing you to build and rebuild infrastructure and applications without performing manual tasks or writing custom scripts
- This also reduces human errors!
Version control like code - By codifying infrastructure, you can treat infrastructure as simple code
- You can write infrastructure with your preferred code editor, check it into a version control system, and review files with team members before deploying to production
- Each code version represents the state of infrastructure, and if issues occur after changes, you can use previous code for quick rollback to previous infrastructure versions

AWS CDK is an open-source software development framework that allows you to model and provision cloud application resources using familiar programming languages!

Cloud application provisioning can be a challenging process that requires:
- Manual tasks, or
- Writing custom scripts, or
- Maintaining templates, or
- Learning domain-specific languages
AWS CDK uses the familiarity and expressiveness of programming languages to model applications
AWS CDK provides high-level components that preconfigure cloud resources with proven defaults, allowing you to build cloud applications even if you're not an expert