Kubernetes集群中怎么利用CRD 實現分批發布

這篇文章給大家介紹Kubernetes集群中怎么利用CRD 實現分批發布，內容非常詳細，感興趣的小伙伴們可以參考借鑒，希望對大家能有所幫助。

使用kubectl進行分批發布

新集群默認安裝了alicloud-application-controller，老集群請先手動安裝，安裝方式，
kubectl create -f alicloud-application-controller.yml

apiVersion: extensions/v1beta1
kind: Deploymentmetadata:
  name: alicloud-application-controller
  labels:
    owner: aliyun
    app: alicloud-application-controller
  namespace: kube-systemspec:
  replicas: 1
  selector:
    matchLabels:
      owner: aliyun
      app: alicloud-application-controller
  template:
    metadata:
      labels:
        owner: aliyun
        app: alicloud-application-controller
      annotations:
        scheduler.alpha.kubernetes.io/critical-pod: ''
    spec:
      tolerations:
      - effect: NoSchedule
        operator: Exists
        key: node-role.kubernetes.io/master
      - effect: NoSchedule
        operator: Exists
        key: node.cloudprovider.kubernetes.io/uninitialized
      containers:
        - name: alicloud-application-controller
          image: registry.cn-hangzhou.aliyuncs.com/acs/aliyun-app-lifecycle-manager:0.1-93095ba
          imagePullPolicy: IfNotPresent
      serviceAccount: admin

我們這里以下面這個StatefulSet為例子演示分批發布的流程，

apiVersion: apps/v1
kind: StatefulSetmetadata:
  name: webspec:
  selector:
    matchLabels:
      app: nginx # has to match .spec.template.metadata.labels
  serviceName: "nginx"
  replicas: 3 # by default is 1
  template:
    metadata:
      labels:
        app: nginx # has to match .spec.selector.matchLabels
    spec:
      terminationGracePeriodSeconds: 10
      containers:
      - name: nginx
        image: registry.cn-hangzhou.aliyuncs.com/xianlu/old-nginx
        ports:
        - containerPort: 80
          name: web

這是一個含有三個實例的nginx 實例，為了暴露此容器，我們使用Service來暴露，Service的Yaml如下

apiVersion: v1
kind: Servicemetadata:
  name: nginx
  labels:
    app: nginxspec:
  ports:
  - port: 80
    name: web
  selector:
    app: nginx
  type: LoadBalancer

這里通過SLB 暴露nginx 服務。
為了保證用戶的Yaml安全性，分批發布需要使用Secret來存儲最終的yaml，這里需要將yaml執行一下base64操作，再存儲。
這個是StatefulSet的Secret Yaml

apiVersion: v1
kind: Secretmetadata:
  name: mysts
type: Opaquedata:
  yaml: 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

下面的為Service的Secret Yaml

apiVersion: v1
kind: Secretmetadata:
  name: mysvc
type: Opaquedata:
  yaml: YXBpVmVyc2lvbjogdjEKa2luZDogU2VydmljZQptZXRhZGF0YToKICBuYW1lOiBuZ2lueAogIGxhYmVsczoKICAgIGFwcDogbmdpbngKc3BlYzoKICBwb3J0czoKICAtIHBvcnQ6IDgwCiAgICBuYW1lOiB3ZWIKICBzZWxlY3RvcjoKICAgIGFwcDogbmdpbngKICB0eXBlOiBMb2FkQmFsYW5jZXI=

分別將上面的兩個Secret 創建出來，kubectl create -f xxxxx

cdn.com/a20640c6e505c48a39cec1b05f30d748796d2221.png">

可以看到兩個Secret都已經創建完畢，下面就可以來創建分批發布的 CRD。分批發布的 CRD 格式如下，

apiVersion: alicloud.com/v1beta1
kind: BatchReleasemetadata:
  name: example-batch-release
  annotations:
    aliyun.batchnum: "2"spec:
  statefulSetSecretName: mysts
  serviceSecretName: mysvc

?aliyun.batchnum: 代表分幾批發布，目前默認是2批
statefulSetSecretName: 表示存儲StatefulSet的Secret 名稱
serviceSecretName: 表示存儲Service的Secret 名稱
使用kubectl create -f xxx 創建此CRD分批發布

可以看到，描述資源都已經創建出來了。

[root@iZbp11x2k7by5gfy6pkrl1Z ~]# kubectl get stsNAME      DESIRED   CURRENT   AGE
web       3         3         6m
[root@iZbp11x2k7by5gfy6pkrl1Z ~]# kubectl get pods -o=wideNAME      READY     STATUS    RESTARTS   AGE       IP             NODE
web-0     1/1       Running   0          7m        172.16.2.2     cn-hangzhou.i-bp199b7a244chaux4ozh
web-1     1/1       Running   0          6m        172.16.2.131   cn-hangzhou.i-bp199b7a244chaux4ozi
web-2     1/1       Running   0          6m        172.16.1.136   cn-hangzhou.i-bp199b7a244chaux4ozg
[root@iZbp11x2k7by5gfy6pkrl1Z ~]# kubectl get svcNAME         TYPE           CLUSTER-IP      EXTERNAL-IP      PORT(S)        AGE
kubernetes   ClusterIP      172.19.0.1      <none>           443/TCP        4h
nginx        LoadBalancer   172.19.12.163   120.55.148.238   80:32065/TCP   7m
[root@iZbp11x2k7by5gfy6pkrl1Z ~]# curl 120.55.148.238old

可以看到，nginx 的StatefulSet和對應的Service 都已經創建出來，并且curl 是可以直接訪問。

下面我們開始分批發布一個新版本的StatefulSet，這里我們新的StatefulSet Yaml 模板如下

apiVersion: apps/v1
kind: StatefulSet
metadata:
  name: web
spec:
  selector:
    matchLabels:
      app: nginx # has to match .spec.template.metadata.labels
  serviceName: "nginx"
  replicas: 3 # by default is 1
  template:
    metadata:
      labels:
        app: nginx # has to match .spec.selector.matchLabels
    spec:
      terminationGracePeriodSeconds: 10
      containers:
      - name: nginx
        image: registry.cn-hangzhou.aliyuncs.com/xianlu/new-nginx
        ports:
        - containerPort: 80
          name: web

可以看到，新老StatefulSet的區別在于，更換了新版本的鏡像。
同樣，我們需要創建一個Secret 來存儲這個新的StatefulSet

apiVersion: v1
kind: Secretmetadata:
  name: my-new-sts
type: Opaquedata:
  yaml: 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

然后我們更新剛才創建的 CRD，將statefulSetSecretName改成新的StatefulSet名稱。
修改后的CRD Yaml 如下:

[root@iZbp11x2k7by5gfy6pkrl1Z ~]# kubectl get BatchRelease example-batch-release -o=yaml
apiVersion: alicloud.com/v1beta1
kind: BatchRelease
metadata:
  annotations:
    aliyun.batchnum: "2"
  clusterName: ""
  creationTimestamp: 2018-07-31T08:17:17Z
  generation: 1
  name: example-batch-release  namespace: default
  resourceVersion: "43484"
  selfLink: /apis/alicloud.com/v1beta1/namespaces/default/batchreleases/example-batch-release
  uid: 2386ddfd-949a-11e8-a3c2-00163e086528spec:
  serviceSecretName: mysvc
  statefulSetSecretName: my-new-sts

[root@iZbp11x2k7by5gfy6pkrl1Z ~]# kubectl describe BatchRelease example-batch-releaseName:         example-batch-release
Namespace:    default
Labels:       <none>
Annotations:  aliyun.batchnum=2API Version:  alicloud.com/v1beta1
Kind:         BatchRelease
Metadata:
  Cluster Name:
  Creation Timestamp:  2018-07-31T08:17:17Z
  Generation:          1
  Resource Version:    43484
  Self Link:           /apis/alicloud.com/v1beta1/namespaces/default/batchreleases/example-batch-release
  UID:                 2386ddfd-949a-11e8-a3c2-00163e086528
Spec:
  Service Secret Name:       mysvc
  Stateful Set Secret Name:  my-new-sts
Status:
  Control:
  Release:
    Batch _ Order:  1
    Progress:       finished
    Status:         WaitingForConfirm
  Resources:
    Service:
      Name:       nginx
      Namespace:  default
      Status:     Updating
    Stateful Set:
      Name:       web
      Namespace:  default
      Status:     Updating
Events:
  Type    Reason             Age   From               Message
  ----    ------             ----  ----               -------
  Normal  CreateSubResource  2m    aliyun-controller  Create StatefulSet resource sucessfully
  Normal  CreateSubResource  2m    aliyun-controller  Create service resource sucessfully
  Normal  Synced             2m    aliyun-controller  Batch CRD synced successfully
  Normal  UpdateResource     1m    aliyun-controller  Begin to update StatefulSet web with partition 2
  Normal  UpdateResource     1m    aliyun-controller  Waiting StatefulSet default:web ready, readyReplicas 2 replicas 3 times 1
  Normal  UpdateResource     1m    aliyun-controller  Waiting StatefulSet default:web ready, readyReplicas 2 replicas 3 times 2
  Normal  UpdateResource     1m    aliyun-controller  Begin to update service with new selector map[app:nginx aliyun.version:2]
  Normal  UpdateResource     1m    aliyun-controller  Update StatefulSet and Service sucessfully, waiting confirm
[root@iZbp11x2k7by5gfy6pkrl1Z ~]# kubectl get pods -o=wideNAME      READY     STATUS    RESTARTS   AGE       IP             NODE
web-0     1/1       Running   0          2m        172.16.2.132   cn-hangzhou.i-bp199b7a244chaux4ozi
web-1     1/1       Running   0          2m        172.16.2.3     cn-hangzhou.i-bp199b7a244chaux4ozh
web-2     1/1       Running   0          1m        172.16.1.138   cn-hangzhou.i-bp199b7a244chaux4ozg
[root@iZbp11x2k7by5gfy6pkrl1Z ~]# kubectl get svcNAME         TYPE           CLUSTER-IP     EXTERNAL-IP      PORT(S)        AGE
kubernetes   ClusterIP      172.19.0.1     <none>           443/TCP        5h
nginx        LoadBalancer   172.19.2.184   101.37.107.187   80:32173/TCP   2m[root@iZbp11x2k7by5gfy6pkrl1Z ~]# curl 101.37.107.187new
[root@iZbp11x2k7by5gfy6pkrl1Z ~]#

我們可以通過event 看到 CRD 的所有事件。同時可以看到，nginx的3個pod，已經有一個 pod發生了改變，變成了最新鏡像，同時 curl對應的service，會發現流量已經指向了新的pod。這樣用戶就可以快速試錯了。

下面我們來演示如何快速回滾，如果流量打到新的 pod后發現有問題，需要回滾，那么我們需要編輯CRD,

將Status 的action 置為rollback 就可以快速回滾。

[root@iZbp11x2k7by5gfy6pkrl1Z ~]# kubectl edit BatchRelease example-batch-releasebatchrelease.alicloud.com "example-batch-release" edited
[root@iZbp11x2k7by5gfy6pkrl1Z ~]# kubectl get pods -o=wideNAME      READY     STATUS    RESTARTS   AGE       IP             NODE
web-0     1/1       Running   0          7m        172.16.2.132   cn-hangzhou.i-bp199b7a244chaux4ozi
web-1     1/1       Running   0          7m        172.16.2.3     cn-hangzhou.i-bp199b7a244chaux4ozh
web-2     1/1       Running   0          3s        172.16.1.139   cn-hangzhou.i-bp199b7a244chaux4ozg
[root@iZbp11x2k7by5gfy6pkrl1Z ~]# kubectl get svcNAME         TYPE           CLUSTER-IP     EXTERNAL-IP      PORT(S)        AGE
kubernetes   ClusterIP      172.19.0.1     <none>           443/TCP        5h
nginx        LoadBalancer   172.19.2.184   101.37.107.187   80:32173/TCP   7m
[root@iZbp11x2k7by5gfy6pkrl1Z ~]# curl 101.37.107.187old

可以看到原來web-2所在的pod已經被回滾到了老鏡像，現在curl service 也都是老的服務了。

發布第二批

發布第二批需要在action 置為continue 就可以

[root@iZbp11x2k7by5gfy6pkrl1Z ~]# kubectl get pods -o=wide
NAME      READY     STATUS    RESTARTS   AGE       IP             NODE
web-0     1/1       Running   0          3s        172.16.2.138   cn-hangzhou.i-bp199b7a244chaux4ozi
web-1     1/1       Running   0          13s       172.16.2.12    cn-hangzhou.i-bp199b7a244chaux4ozh
web-2     1/1       Running   0          2m        172.16.1.153   cn-hangzhou.i-bp199b7a244chaux4ozg
[root@iZbp11x2k7by5gfy6pkrl1Z ~]# kubectl get BatchRelease example-batch-release -o=yaml
apiVersion: alicloud.com/v1beta1
kind: BatchRelease
metadata:
  annotations:
    aliyun.batchnum: "2"
  clusterName: ""
  creationTimestamp: 2018-07-31T09:44:58Z
  generation: 1
  name: example-batch-release  namespace: default
  resourceVersion: "58066"
  selfLink: /apis/alicloud.com/v1beta1/namespaces/default/batchreleases/example-batch-release
  uid: 6321dcaf-94a6-11e8-a3c2-00163e086528spec:
  serviceSecretName: mysvc
  statefulSetSecretName: my-new-sts
status:
  control: {}
  release:
    batch_order: "2"
    progress: finished
    status: WaitingForConfirm
  resources:
    Service:
      name: nginx      namespace: default
      status: Updating
    StatefulSet:
      name: web      namespace: default
      status: Updating

可以看到StatefulSet的三個 pod都被更新了。

這個時候就可以確認發布了

置為confirm 就確定了這次發布。

[root@iZbp11x2k7by5gfy6pkrl1Z ~]# kubectl get BatchRelease example-batch-release -o=yaml
apiVersion: alicloud.com/v1beta1
kind: BatchRelease
metadata:
  annotations:
    aliyun.batchnum: "2"
  clusterName: ""
  creationTimestamp: 2018-07-31T09:44:58Z
  generation: 1
  name: example-batch-release  namespace: default
  resourceVersion: "58542"
  selfLink: /apis/alicloud.com/v1beta1/namespaces/default/batchreleases/example-batch-release
  uid: 6321dcaf-94a6-11e8-a3c2-00163e086528spec:
  serviceSecretName: mysvc
  statefulSetSecretName: my-new-sts
status:
  control: {}
  release:
    progress: finished
    status: Success
  resources:
    Service:
      name: nginx      namespace: default
      status: Success
    StatefulSet:
      name: web      namespace: default
      status: Success
[root@iZbp11x2k7by5gfy6pkrl1Z ~]# kubectl get secret -l owner=aliyun -n=kube-system
NAME                       TYPE      DATA      AGE
example-batch-release.v1   Opaque    4         18m
example-batch-release.v2   Opaque    4         56s

關于Kubernetes集群中怎么利用CRD 實現分批發布就分享到這里了，希望以上內容可以對大家有一定的幫助，可以學到更多知識。如果覺得文章不錯，可以把它分享出去讓更多的人看到。