kubernetes get -o yaml - Shell-Bash

简介

Kubernetes是一款支持容器化技术的自动化部署系统，旨在简化容器化应用程序的部署、扩展和管理。其中，kubernetes get -o yaml 是一条命令行指令，在Shell-Bash环境中使用，它可以帮助开发者获得Kubernetes API对象的详细信息，以一份YAML文件格式的形式返回。

语法

kubectl get [-f filename] [(-o|--output=)json|yaml|wide|custom-columns=...] [--no-headers] [-w|--watch] [-a|--all-namespaces] [-A|--all] 

参数说明

• -f --filename：使用指定的文件名或标准输入获取Kubernetes API的对象
• -o --output：输出格式
• json：以JSON格式显示数据
• yaml：以YAML格式显示数据
• wide：以更加详细的方式显示数据
• custom-columns：自定义列显示格式
• --no-headers：在输出结果中省略表头
• -w --watch：持续观察状态变化
• -a --all-namespaces：列出所有的命名空间
• -A --all：列出所有的所有资源

使用范例

以下范例将获取 Kubernetes Pod 的详细信息，并将结果以 YAML 格式返回：

kubectl get pods my-pod -o yaml

返回的结果将如下所示：

```yaml
apiVersion: v1
kind: Pod
metadata:
  annotations:
    kubernetes.io/psp: eks.privileged
    kubectl.kubernetes.io/last-applied-configuration: |
      {"apiVersion":"v1","kind":"Pod","metadata":{"annotations":{},"labels":{"app":"my-app"},"name":"my-pod","namespace":"default"},"spec":{"containers":[{"image":"nginx","name":"my-container","ports":[{"containerPort":80,"name":"http","protocol":"TCP"}]}]}}
  creationTimestamp: "2021-08-02T12:46:05Z"
  labels:
    app: my-app
  name: my-pod
  namespace: default
  resourceVersion: "4446547"
  uid: 6a8c75cf-ad00-48e5-b5d5-b40fc8e5fc16
spec:
  containers:
  - image: nginx
    imagePullPolicy: Always
    name: my-container
    ports:
    - containerPort: 80
      name: http
      protocol: TCP
    resources:
      limits:
        cpu: "2"
        memory: 2Gi
      requests:
        cpu: "1"
        memory: 1Gi
    terminationMessagePath: /dev/termination-log
    terminationMessagePolicy: File
    volumeMounts:
    - mountPath: /var/run/secrets/kubernetes.io/serviceaccount
      name: my-token-hnvhb
      readOnly: true
  dnsPolicy: ClusterFirst
  enableServiceLinks: true
  nodeName: ip-10-0-1-197.us-west-2.compute.internal
  preemptionPolicy: PreemptLowerPriority
  priority: 0
  restartPolicy: Always
  schedulerName: default-scheduler
  securityContext:
    fsGroup: 1000
    runAsGroup: 1000
    runAsNonRoot: false
    runAsUser: 1000
  serviceAccount: my-token-hnvhb
  serviceAccountName: my-token-hnvhb
  terminationGracePeriodSeconds: 30
  tolerations:
  - effect: NoExecute
    key: node.kubernetes.io/not-ready
    operator: Exists
    tolerationSeconds: 50
  - effect: NoExecute
    key: node.kubernetes.io/unreachable
    operator: Exists
    tolerationSeconds: 50
  volumes:
  - name: my-token-hnvhb
    secret:
      defaultMode: 420
      secretName: my-token-hnvhb
status:
  conditions:
  - lastProbeTime: null
    lastTransitionTime: "2021-08-02T12:46:05Z"
    status: "True"
    type: Initialized
  - lastProbeTime: null
    lastTransitionTime: "2021-08-02T12:46:29Z"
    status: "True"
    type: Ready
  - lastProbeTime: null
    lastTransitionTime: "2021-08-02T12:46:29Z"
    status: "True"
    type: ContainersReady
  - lastProbeTime: null
    lastTransitionTime: "2021-08-02T12:46:05Z"
    status: "True"
    type: PodScheduled
  containerStatuses:
  - containerID: docker://62e2caf6cf089f6bf1aab709bbe8f61c3f6eba56ab9d05e5865b5a5ed5a5a5c5
    image: nginx
    imageID: docker-pullable://nginx@sha256:e7d00cf1e05d7f6b2d4ea1284bd4e45d1badd9dedad75762b1fbe15b3e139ee7
    name: my-container
    ready: true
    restartCount: 0
    started: true
    state:
      running:
        startedAt: "2021-08-02T12:46:28Z"
  hostIP: 10.0.1.197
  phase: Running
  podIP: 10.0.1.80
  podIPs:
  - ip: 10.0.1.80
  qosClass: BestEffort
  startTime: "2021-08-02T12:46:05Z"

总结

kubernetes get -o yaml 向开发者提供了获取 Kubernetes API 对象详细信息的途径，同时将信息以 YAML 格式返回。使用该指令可以使开发者更加清晰地了解 Kubernetes 应用程序的表现和运作情况。