Deployment を使ってみる (kubernetes)

kubernetes

Published: 2020-12-29

やったこと

Deployment を使ってみます。

確認環境

$ k version
Client Version: version.Info{Major:"1", Minor:"16", GitVersion:"v1.16.2", GitCommit:"c97fe5036ef3df2967d086711e6c0c405941e14b", GitTreeState:"clean", BuildDate:"2019-10-15T19:18:23Z", GoVersion:"go1.12.10", Compiler:"gc", Platform:"darwin/amd64"}
Server Version: version.Info{Major:"1", Minor:"19", GitVersion:"v1.19.3", GitCommit:"1e11e4a2108024935ecfcb2912226cedeafd99df", GitTreeState:"clean", BuildDate:"2020-10-14T12:41:49Z", GoVersion:"go1.15.2", Compiler:"gc", Platform:"linux/amd64"}

調査

sample3.yaml

apiVersion: apps/v1
kind: Deployment
metadata:
  name: my-deployment-first
spec:
  replicas: 2
  selector:
    matchLabels:
      app: sample3
  template:
    metadata:
      labels:
        app: sample3
    spec:
      containers:
        - name: nginx-container
          image: nginx:1.16

マニフェストの適用

$ k apply -f sample3.yaml
deployment.apps/my-deployment-first created

$ k get deployments
NAME                  READY   UP-TO-DATE   AVAILABLE   AGE
my-deployment-first   2/2     2            2           78s
$ k get rs
NAME                             DESIRED   CURRENT   READY   AGE
my-deployment-first-55df95dccf   2         2         2       3m37s
$ k get pods
NAME                                   READY   STATUS    RESTARTS   AGE
my-deployment-first-55df95dccf-8d9ld   1/1     Running   0          92s
my-deployment-first-55df95dccf-pcmr8   1/1     Running   0          90s

sample3.yaml を編集します。

          image: nginx:1.17

$ k apply -f sample3.yaml
deployment.apps/my-deployment-first configured
$ k get deployments
NAME                  READY   UP-TO-DATE   AVAILABLE   AGE
my-deployment-first   2/2     0            2           20m
$ k get rs
NAME                             DESIRED   CURRENT   READY   AGE
my-deployment-first-55df95dccf   2         2         2       5m19s
my-deployment-first-5b8875c9cb   1         1         0       20m
$ k get pods
NAME                                   READY   STATUS              RESTARTS   AGE
my-deployment-first-55df95dccf-8d9ld   1/1     Running             0          2m48s
my-deployment-first-55df95dccf-pcmr8   1/1     Running             0          2m46s
my-deployment-first-5b8875c9cb-qp66z   0/1     ContainerCreating   0          0s

更新戦略の確認 ( .spec.strategy )

Recreate
RollingUpdate (デフォルト)

$ k get deployment -o jsonpath="{.items[*].spec.strategy}"
map[rollingUpdate:map[maxSurge:25% maxUnavailable:25%] type:RollingUpdate]

参考

Deployment | Kubernetes