Amazon EKS - Elastic Kubernetes Service

• It is a way to launch managed Kubernetes clusters on AWS
• Kubernetes is an open-source system for automatic deployment, scaling and management of containerized (usually Docker) applications
• It is an alternative to ECS, having similar goal but different API
• EKS supports EC2 launch mode if we want to deploy worker nodes or Fargate to deploy serverless containers
• Use case for EKS: if our company already is using Kubernetes on-premises on on another cloud and wants to migrate to AWS
• Kubernetes is cloud-agnostic, can be used in any cloud (Azure, GCP, etc.)

EKS Node Types

• Managed Node Groups:
  • Creates and manages Nodes (EC2 instances) for us
  • Nodes are part of an ASG managed by EKS
  • Supports On-Demand or Spot Instances
• Self-Managed Nodes:
  • Nodes are created by us and registered to the EKS cluster
  • We can the use prebuilt AMI - Amazon EKS Optimized AMI; or we can build our own AMI
  • Supports On-Demand and Spot Instances
• AWS Fargate:
  • No maintenance required; no nodes to manage

Data Volumes

• To attach a volume we need to specify a StorageClass in the manifest on our EKS cluster
• This will leverage a Container Storage Interface (CSI) compliant driver
• We have support for:
  • Amazon EBS
  • Amazon EFS (only type which works with Fargate)
  • Amazon FSx for Lustre
  • Amazon FSx for NetApp ONTAP

Control Plane Logging

• Send EKS Control Plane audit and diagnostic logs to CloudWatch Logs
• EKS Control Plane log entry types:
  • API Server (api)
  • Audit (audit)
  • Authenticator (authenticator)
  • Controller Manager (controllerManager)
  • Scheduler (scheduler)
• We have the ability to select which kind of logs we want to send to CloudWatch Logs

Nodes and Container Logging

• We can capture node, pod and container logs and sent them to CloudWatch Logs
• We have to use the CloudWatch Agent to send metrics to CloudWatch
• To get the logs we can use FluentBit or Fluentd log drivers
• Container logs are stored on a Node directory /var/log/container
• We can use CloudWatch Container Insights to get a dashboarding monitoring solution for nodes, pods, tasks and services