Deloyment 사용하기

Deloyment 
1)Deployment -> ReplicaSet-> pod 컨트롤
-ReplicaSet 을 컨트롤해서 Pod 수를 조정
-Rolling Update & Rolling Back
 
-Rolling Update & Rolling Back란
목표
kubectl을 이용하여 롤링 업데이트 수행하기
애플리케이션 업데이트하기
사용자들은 애플리케이션이 항상 가용한 상태일 것이라 여기고 개발자들은 하루에 여러번씩 새로운 버전을 배포하도록 요구 받고있다. 쿠버네티스에서는 이것을 롤링 업데이트를 통해 이루고 있다. 롤링 업데이트는 파드 인스턴스를 점진적으로 새로운 것으로 업데이트하여 디플로이먼트 업데이트가 서비스 중단 없이 이루어질 수 있도록 해준다. 새로운 파드는 가용한 자원을 보유한 노드로 스케줄될 것이다.
* ps https://kubernetes.io/ko/docs/tutorials/kubernetes-basics/update/update-intro/
두개의 yaml파일을 비교 합니다 

apiVersion: apps/v1 kind: ReplicaSet metadata:   name: rs-nginx spec:   replicas: 3   selector:     matchLabels:       app: webui   template:     metadata:       name: nginx-pod       labels:         app: webui     spec:       containers:       - name: nginx-container         image: nginx:1.14

apiVersion: apps/v1 kind: Deloyment metadata:   name: deploy-nginx spec:   replicas: 3   selector:     matchLabels:       app: webui   template:     metadata:       name: nginx-pod       labels:         app: webui     spec:       containers:       - name: nginx-container         image: nginx:1.14

                  

# vi deploy-nginx.yaml

apiVersion: apps/v1 kind: Deployment metadata:   name: deploy-nginx spec:   replicas: 3   selector:     matchLabels:       app: webui   template:     metadata:       name: nginx-pod       labels:         app: webui     spec:       containers:       - name: nginx-container         image: nginx:1.14

 

# kubectl create -f deploy-nginx.yaml  deployment.apps/deploy-nginx created

  

# kubectl get pods -o wide NAME                           READY   STATUS    RESTARTS   AGE   IP             NODE      NOMINATED NODE   READINESS GATES deploy-nginx-bd76d5967-945ds   1/1     Running   0          20s   10.101.1.150   worker2               deploy-nginx-bd76d5967-pgm9w   1/1     Running   0          20s   10.101.1.97    worker1               deploy-nginx-bd76d5967-qcbg8   1/1     Running   0          20s   10.101.1.96    worker1

전체 보기 명령어 

# watch kubectl get deploy,rs,pod

Every 2.0s: kubectl get deploy,rs,pod                                                                    master: Fri Sep  8 13:27:33 2023 NAME                           READY   UP-TO-DATE   AVAILABLE   AGE deployment.apps/deploy-nginx   3/3     3            3           2m4s NAME                                     DESIRED   CURRENT   READY   AGE replicaset.apps/deploy-nginx-bd76d5967   3         3         3       2m4s NAME                               READY   STATUS    RESTARTS   AGE pod/deploy-nginx-bd76d5967-945ds   1/1     Running   0          2m4s pod/deploy-nginx-bd76d5967-pgm9w   1/1     Running   0          2m4s pod/deploy-nginx-bd76d5967-qcbg8   1/1     Running   0          2m4s

순서대로 확인 가능하다.
pod/deploy-nginx-bd76d5967-945ds 
디플로이먼트        레플리카    파드 

삭제 시도 시 
디플로이먼트를 지워야지만 다지워집니다.

# kubectl delete deployment.apps deploy-nginx deployment.apps "deploy-nginx" deleted

Deployment Rolling Update & Rolling Back란 Roling update   - kubectl set image deployment <deploy_name> <container_name> = <new_virsion_image> rollback  - kucuctl rollout history deployment <deploy_name>  - kucuctl rollout undo deploy <deploy_name>

롤링 업데이트 및 복원 진행입니다. 

deplotment   app

replica=3 nginx=1.14

ReplicaSet xxx   1.14 x 3

kubectl set image deployment app-deploy app=nginx:1.15--record

ReplicaSet yyy  하나씩 xxx(1.14) 서버가 사라지고 하나씩 yyy(1.15)서버가 늘어난다

# vi deployment-exam1.yaml apiVersion: apps/v1 kind: Deployment metadata:   name: app-deploy spec:   selector:     matchLabels:       app: webui   replicas: 3   template:     metadata:       labels:         app: webui     spec:       containers:       - image: nginx:1.14         name: web         ports:         -containerPort: 80

 

# kubectl create -f deployment-exam1.yaml  deployment.apps/app-deploy created

 

# kubectl get deploy,rs,pod NAME                         READY   UP-TO-DATE   AVAILABLE   AGE deployment.apps/app-deploy   3/3     3            3           29s NAME                                   DESIRED   CURRENT   READY   AGE replicaset.apps/app-deploy-d599fcdf4   3         3         3       29s NAME                             READY   STATUS    RESTARTS   AGE pod/app-deploy-d599fcdf4-bcc85   1/1     Running   0          29s pod/app-deploy-d599fcdf4-kpq9b   1/1     Running   0          29s pod/app-deploy-d599fcdf4-lc46z   1/1     Running   0          29s

 

# kubectl describe pod/app-deploy-d599fcdf4-lc46z ...     Image:          nginx:1.14 ... 버전확인 가능

# kubectl rollout history deployment app-deploy deployment.apps/app-deploy  REVISION  CHANGE-CAUSE 1              <none> --record 옵션 안쓰면 히스토리 확인 불가  # kubectl delete -f deployment-exam1.yaml  삭제

 

# kubectl create -f deployment-exam1.yaml --record Flag --record has been deprecated, --record will be removed in the future deployment.apps/app-deploy created

# kubectl rollout history deployment app-deploy deployment.apps/app-deploy  REVISION  CHANGE-CAUSE 1         kubectl create --filename=deployment-exam1.yaml --record=true

# kubectl set image deploy app-deploy web=nginx:1.15 --record 실행시

 

# kubectl describe pod/app-deploy-854cc64799-t7dr2 ...     Image:          nginx:1.15 ... 변환된걸 볼수있다 .

# kubectl set image deploy app-deploy web=nginx:1.16 --record 실행시  업데이트 이력  # kubectl rollout history deployment app-deploy deployment.apps/app-deploy  REVISION  CHANGE-CAUSE 1         kubectl create --filename=deployment-exam1.yaml --record=true 2         kubectl set image deploy app-deploy web=nginx:1.15 --record=true 3         kubectl set image deploy app-deploy web=nginx:1.16 --record=true

rolling 멈춤 재시작 명령어 

# kubectl rollout pause deploymnet app-deploy   멈춤  # kubectl rollout resumed deploymnet app-deploy 재시작

# vi deployment-exam2.yaml

apiVersion: apps/v1 kind: Deployment metadata:   name: deploy-nginx   annotations:     kubernetes.io/change-cause: version 1.14 spec:   progressDeadlineSeconds: 600   revisionHistoryLimit: 10   strategy:     rollingUpdate:       maxSurge: 25%       maxUnavailable: 25%     type: RollingUpdate   replicas: 3   selector :     matchLabels:       app: webui   template:     metadata:       labels:         app: webui     spec:       containers:       - image: nginx:1.14         name: web         ports:         - containerPort: 80

# kubectl rollout history deployment app-deploy deployment.apps/app-deploy  REVISION  CHANGE-CAUSE 1         kubectl create --filename=deployment-exam1.yaml --record=true 2         kubectl set image deploy app-deploy web=nginx:1.15 --record=true 3         kubectl set image deploy app-deploy web=nginx:1.16 --record=true

# kubectl rollout undo deployment app-deploy --to-revision=2

# kubectl rollout history deployment app-deploy deployment.apps/app-deploy  REVISION  CHANGE-CAUSE 1         kubectl create --filename=deployment-exam1.yaml --record=true 3         kubectl set image deploy app-deploy web=nginx:1.16 --record=true 4         kubectl set image deploy app-deploy web=nginx:1.15 --record=true

변경된것을 볼수있습니다 .


yaml파일을 통해 롤링 작업 

# vi deployment-exam2.yaml apiVersion: apps/v1 kind: Deployment metadata:   name: deploy-nginx   annotations:     kubernetes.io/change-cause: version 1.14 spec:   progressDeadlineSeconds: 600   revisionHistoryLimit: 10   strategy:     rollingUpdate:       maxSurge: 25%       maxUnavailable: 25%     type: RollingUpdate   replicas: 3   selector :     matchLabels:       app: webui   template:     metadata:       labels:         app: webui     spec:       containers:       - image: nginx:1.14         name: web         ports:         - containerPort: 80

# kubectl apply -f deployment-exam2.yaml  deployment.apps/deploy-nginx created

 

# kubectl describe pod deploy-nginx-d599fcdf4-nwqdl     kubernetes.io/change-cause: version 1.15       - image: nginx:1.15 로 변경

 

# kubectl apply -f deployment-exam2.yaml  deployment.apps/deploy-nginx configured

이력  # kubectl rollout history deployment deploy-nginx  deployment.apps/deploy-nginx  REVISION  CHANGE-CAUSE 1         version 1.14 2         version 1.15

# kubectl delete deployment.apps deploy-nginx deployment.apps "deploy-nginx" deleted