[6] Deployment & Pod Scale

1. Pod Scale out

❓Pod Scale Out

• Expand the number of running pods in “eshop-order” to 5.
  • 작업 클러스터: k8s
  • namespace: devops
  • deployment: eshop-order

Reference

docs에서 reference 검색 → scale

Kubectl Reference Docs

실습

# 작업 클러스터 이동
[user@console ~]$ kubectl config use-context k8s

# devops라는 namespace가 있는지 확인
[user@console ~]$ kubectl get namespaces devops

# namespace가 devops인 곳에서 deployment가 있는지 확인
# 확인했을 때 2개의 pod가 돌아가고 있는거 확인
[user@console ~]$ kubectl get deployments.app -n devops
NAME           READY
eshop-order    2/2

# Deployment의 ReplicaSet을 5로 늘려준다
[user@console ~]$ kubectl scale deployment eshop-order -n devops --replicas=5

# 확인했을 때 5개의 pod가 돌아가고 있는거 확인
[user@console ~]$ kubectl get deployments.app -n devops
NAME           READY
eshop-order    5/5

2. deployment 생성하고 scaling하기

❓deployment 생성하고 scaling하기

• create a deployment as follows:
  • 작업 클러스터: k8s
  • TASK:
    • name: webserver
    • 2 replicas
    • label: app_env_stage=dev
    • container name: webserver
    • container image: nginx:1.14
  • Scale Out deployment
    • Scale the deployment webserver to 3 pods

실습

# 조건에 맞게 deployment 생성
# webserver.yaml 파일로 YAML 파일 생성
[user@console ~]$ kubectl create deployment webserver --image=nginx:1.14 --replicas=2 --dry-run=client -o yaml > webserver.yaml

# webserver.yaml 파일 수정
[user@console ~]$ vi webserver.yaml

matchLabels:
	app: webserver
되어있는 부분을 아래처럼 수정하기
matchLabels:
	app_env_stage: dev
로 수정하기

밑에 metadata에 해당하는 labels 부분도 수정하기

container부분에 name webserver로 수정하기

:wq

# 수정한 yaml파일 실행
[user@console ~]$ kubectl apply -f webserver.yaml

# 확인
[user@console ~]$ kubectl get deployments -o wide

# 3개로 Scale Out
[user@console ~]$ kubectl scale deployments webserver --replicas=3

# 확인 (label 정보까지 포함해서)
[user@console ~]$ kubectl get pods --show-labels

기출문제 (10번)

Task: Scale the deployment webserver to 3 pods.

• 답안

  kubectl get deployments
  --> webserver라는 deployment가 있는지 확인
  

  kubectl scale deployment webserver --replicas=3
  

기출문제 (14번)

Task: Scale the deployment presentation to 6 pods.

• 답안

  # presentation이라는 deployment가 있는지 확인
  kubectl get deployments presentation
  

  kubectl scale deployment presentation --replicas=6
  

기출문제 (65번)

Create a deployment spec file that will: Launch 7 replicas of the nginx Image with the label app_runtime_stage=dev deployment name: kual00201.

Save a copy of this spec file to /opt/KUAL00201/spec_deployment.yaml (or /opt/KUAL00201/spec_deployment.json). When you are done, clean up (delete) any new Kubernetes API object that you produced during this task.

• 답안
  

  kubectl create deploy kual00201 --image=nginx --dry-run=client -o yaml > /opt/KUAL00201/spec_deployment.yaml
  

  vi /opt/KUAL00201/spec_deployment.yaml
  
  apiVersion: apps/v1
  kind: Deployment
  metadata:
    creationTimestamp: null
    labels:
      app_runtime_stage: dev
    name: kual00201
  spec:
    replicas: 7
    selector:
      matchLabels:
        app_runtime_stage: dev
    strategy: {}
    template:
      metadata:
        creationTimestamp: null
        labels:
          app_runtime_stage: dev
      spec:
        containers:
        - image: nginx
          name: nginx
          resources: {}
  status: {}
  
  :wq
  

  kubectl apply -f /opt/KUAL00201/spec_deployment.yaml 
  

  # 만들어졌는지 확인
  kubectl get deploy kual00201
  

  # 만든 것 삭제하기
  rm -rf /opt/KUAL00201/spec_deployment.yaml 
  
  kubectl delete deploy kual00201