EC2, ECS, EKS 차이점과 Auto Scaling, Fargate 구성 방법

m5.xlarge
│ │  └── 크기 (nano < micro < small < medium < large < xlarge < 2xlarge ...)
│ └──── 세대 (5세대)
└────── 패밀리 (범용)

# EC2 생성
aws ec2 run-instances \
  --image-id ami-0c55b159cbfafe1f0 \
  --instance-type t3.medium \
  --key-name my-key \
  --security-group-ids sg-xxx \
  --subnet-id subnet-xxx

트래픽 증가 → CPU 80% 넘음 → ASG가 EC2 추가
트래픽 감소 → CPU 30% 이하 → ASG가 EC2 제거

aws ec2 create-launch-template \
  --launch-template-name app-template \
  --launch-template-data '{
    "ImageId": "ami-xxx",
    "InstanceType": "t3.medium",
    "SecurityGroupIds": ["sg-xxx"],
    "KeyName": "my-key"
  }'

aws autoscaling create-auto-scaling-group \
  --auto-scaling-group-name app-asg \
  --launch-template LaunchTemplateName=app-template \
  --min-size 2 \
  --max-size 10 \
  --desired-capacity 3 \
  --vpc-zone-identifier "subnet-a,subnet-c" \
  --target-group-arns "arn:aws:elasticloadbalancing:..."

# ASG 상태 확인
aws autoscaling describe-auto-scaling-groups --auto-scaling-group-names app-asg

ECS Cluster
├── Service (Deployment처럼 Task 수 유지)
│   └── Task (Pod처럼 컨테이너 실행 단위)
│       └── Container
└── Task Definition (Pod 스펙처럼 컨테이너 정의)

{
  "family": "my-app",
  "networkMode": "awsvpc",
  "containerDefinitions": [
    {
      "name": "app",
      "image": "111111111111.dkr.ecr.ap-northeast-2.amazonaws.com/myapp:latest",
      "portMappings": [{ "containerPort": 8080 }],
      "memory": 512,
      "cpu": 256,
      "logConfiguration": {
        "logDriver": "awslogs",
        "options": {
          "awslogs-group": "/ecs/my-app",
          "awslogs-region": "ap-northeast-2",
          "awslogs-stream-prefix": "ecs"
        }
      }
    }
  ],
  "requiresCompatibilities": ["FARGATE"],
  "cpu": "256",
  "memory": "512"
}

AWS가 관리 (Control Plane):
  - API Server
  - etcd
  - Scheduler
  - Controller Manager

직접 관리 (Data Plane):
  - EC2 Node Group (또는 Fargate)
  - Pod, Deployment, Service 등

eksctl create cluster \
  --name my-cluster \
  --region ap-northeast-2 \
  --nodegroup-name workers \
  --node-type t3.medium \
  --nodes 3 \
  --nodes-min 2 \
  --nodes-max 5

aws eks update-kubeconfig --name my-cluster --region ap-northeast-2
kubectl get nodes