Kubernetes로 배포하기, yml 정리

https://subicura.com/k8s/guide/sample.html#%E1%84%8B%E1%85%AF%E1%84%83%E1%85%B3%E1%84%91%E1%85%B3%E1%84%85%E1%85%A6%E1%84%89%E1%85%B3-%E1%84%87%E1%85%A2%E1%84%91%E1%85%A9

웹 애플리케이션 배포

 

 

wordpress 배포

 

wordpress.yml

apiVersion: apps/v1
kind: Deployment # mysql 파드 
metadata:
  name: wordpress-mysql
  labels:
    app: wordpress
spec:
  selector: # Deployment 에서 selector 에는 관리할 pod 을 명시한다 
    matchLabels: # 즉 app:wordpress,tier:mysql 레이블을 갖는 pod 를 이 deployment 가 관리한다는 뜻
      app: wordpress
      tier: mysql
  template: # matchLabels 에 해당하는 pod 없으면 template 에 명시된 내용에 따라 pod 생성함 
    metadata:
      labels:
        app: wordpress
        tier: mysql
    spec:
      containers:
        - image: mariadb:10.7
          name: mysql
          env:
            - name: MYSQL_DATABASE
              value: wordpress
            - name: MYSQL_ROOT_PASSWORD
              value: password
          ports:
            - containerPort: 3306  # 컨테이너가 listen 할 포트 
              name: mysql

---
apiVersion: v1
kind: Service # mysql 접속 위한 ClusterIP 서비스 
metadata:
  name: wordpress-mysql # 서비스가 내부 DNS 에 해당 이름으로 도메인 등록 
  labels:
    app: wordpress
spec: # 타입 지정 안하면 ClusterIP 
  ports:
    - port: 3306 # 3306 포트로 요청 
  # Service에서 selector는 서비스가 트래픽을 라우팅할 파드들의 레이블을 명시한다. 
  # 여기서는 Deployment 와 동일 레이블을 명시해서 해당 deployment가 관리하는(생성하는) 파드
  selector: 
    app: wordpress
    tier: mysql

---
apiVersion: apps/v1
kind: Deployment # wordpress app 파드 
metadata:
  name: wordpress
  labels:
    app: wordpress
spec:
  selector:
    matchLabels:
      app: wordpress
      tier: frontend
  template:
    metadata:
      labels:
        app: wordpress
        tier: frontend
    spec:
      containers:
        - image: wordpress:5.9.1-php8.1-apache
          name: wordpress
          env:
            - name: WORDPRESS_DB_HOST # 서비스가 등록한 도메인으로 설정 
              value: wordpress-mysql
            - name: WORDPRESS_DB_NAME
              value: wordpress
            - name: WORDPRESS_DB_USER
              value: root
            - name: WORDPRESS_DB_PASSWORD
              value: password
          ports:
            - containerPort: 80
              name: wordpress

---
apiVersion: v1
kind: Service # 외부 노출 위한 NodePort 서비스 
metadata:
  name: wordpress
  labels:
    app: wordpress
spec:
  type: NodePort
  ports:
    - port: 80
      nodePort: 30000 # 노드에 오픈되는 포트 
  selector: # 아래 레이블을 갖는 파드와 연결 
    app: wordpress
    tier: frontend

 

 

 

selector

• Deployment 의 selector 는 관리할 pod 를 명시한다
• Service에서 selector는 서비스가 트래픽을 라우팅할 파드들의 레이블을 명시한다

 

apply

 

---

 

Vote

 

vote.yml

# deployment/vote
apiVersion: apps/v1
kind: Deployment
metadata:
  name: vote
spec:
  selector:
    matchLabels:
      service: vote
  template:
    metadata:
      labels:
        service: vote
    spec:
      containers:
        - name: vote
          image: ghcr.io/subicura/voting/vote
          env:
            - name: REDIS_HOST
              value: "redis"
            - name: REDIS_PORT
              value: "6379"
          livenessProbe: # 컨테이너 헬스체크
            httpGet:
              path: /
              port: 80
          readinessProbe:
            httpGet:
              path: /
              port: 80
          ports:
            - containerPort: 80
              protocol: TCP

--- # deployment/vote 를 외부에서 접근 하기위한 NodePort 서비스
apiVersion: v1
kind: Service
metadata:
  name: vote
spec:
  type: NodePort
  ports:
    - port: 80
      nodePort: 31000
      protocol: TCP
  selector:
    service: vote

--- # deployment/result
apiVersion: apps/v1
kind: Deployment
metadata:
  name: result
spec:
  selector:
    matchLabels:
      service: result
  template:
    metadata:
      labels:
        service: result
    spec:
      containers:
        - name: result
          image: ghcr.io/subicura/voting/result
          env:
            - name: POSTGRES_HOST # Postgres 접속 위한 환경변수
              value: "db"
            - name: POSTGRES_PORT
              value: "5432"
          livenessProbe:
            httpGet:
              path: /
              port: 80
          readinessProbe:
            httpGet:
              path: /
              port: 80
          ports:
            - containerPort: 80
              protocol: TCP

--- # deployment/result 외부 접속 용 NodePort
apiVersion: v1
kind: Service
metadata:
  name: result
spec:
  type: NodePort
  ports:
    - port: 80
      nodePort: 31001
      protocol: TCP
  selector:
    service: result

--- # deployment/worker
apiVersion: apps/v1
kind: Deployment
metadata:
  name: worker
spec:
  selector:
    matchLabels:
      service: worker
  template:
    metadata:
      labels:
        service: worker
    spec:
      containers:
        - name: worker
          image: ghcr.io/subicura/voting/worker
          env: # worker 는 redis, postgres 모두 접근 해야함
            - name: REDIS_HOST
              value: "redis"
            - name: REDIS_PORT
              value: "6379"
            - name: POSTGRES_HOST
              value: "db"
            - name: POSTGRES_PORT
              value: "5432"

--- # deployment/redis
apiVersion: apps/v1
kind: Deployment
metadata:
  name: redis
spec:
  selector:
    matchLabels:
      service: redis
  template:
    metadata:
      labels:
        service: redis
    spec:
      containers:
        - name: redis
          image: redis
          ports:
            - containerPort: 6379
              protocol: TCP

--- # redis 접근용 ClusterIP
apiVersion: v1
kind: Service
metadata:
  name: redis
spec:
  ports:
    - port: 6379
      protocol: TCP
  selector:
    service: redis

--- # deployment/db
apiVersion: apps/v1
kind: Deployment
metadata:
  name: db
spec:
  selector:
    matchLabels:
      service: db
  template:
    metadata:
      labels:
        service: db
    spec:
      containers:
        - name: db
          image: postgres:9.4
          env:
            - name: POSTGRES_USER
              value: "postgres"
            - name: POSTGRES_PASSWORD
              value: "postgres"
          ports:
            - containerPort: 5432
              protocol: TCP

--- # deployment/db 접근용 ClusterIP
apiVersion: v1
kind: Service
metadata:
  name: db
spec:
  ports:
    - port: 5432
      protocol: TCP
  selector:
    service: db

 

 

apply

 

 

클러스터 ip:31000

 

클러스터 ip:31001

 

---

정리

해보니까 결국 실제로는 Deployment 와 Service 이 두개를 가장 많이 정의할것 같다.

 

Deployment

# deployment/vote

# kubernetes 의 api 버전을 정의한다.
apiVersion: apps/v1
# Deployment, Service, Pod ... 
kind: Deployment
metadata:
  name: vote
spec:
  # Deployment 에서의 selector 는 내가 (deployment) 가 관리할 pod 를 의미한다
  selector:
    # 레이블 service:vote 인 pod를 관리한다 
    matchLabels:
      service: vote
  # selector 에서 정의한 pod 가 없다면 template 에 정의된 스펙에 따라 새로 만든다 
  template:
    metadata:
      labels:
        service: vote
    spec:
      containers:
        - name: vote
          image: ghcr.io/subicura/voting/vote
          env:
            - name: REDIS_HOST
              value: "redis"
            - name: REDIS_PORT
              value: "6379"
          livenessProbe: # 컨테이너 헬스체크
            httpGet:
              path: /
              port: 80
          readinessProbe:
            httpGet:
              path: /
              port: 80
          ports:
            - containerPort: 80
              protocol: TCP

 

Service

--- # deployment/vote 를 외부에서 접근 하기위한 NodePort 서비스
apiVersion: v1
kind: Service
metadata:
  name: vote
spec:
  # ClusterIP, NodePort... type 정의 하지 않으면 기본 ClusterIP 
  type: NodePort  
  ports:
      # 클러스터 내에서 서비스에 엑세스할 포트 번호 
    - port: 80 
      # 노드들인 이 포트 번호로 외부에서 접근 가능하다 
      nodePort: 31000 
      protocol: TCP
  selector:
    service: vote