kubernetes实践-入门与环境搭建

灰太狼 2022-06-10 20:12 284阅读 0赞

> Kubernetes is an open-source system for automating deployment, scaling, and management of containerized applications.

Kubernetes官网地址[https://kubernetes.io/][https_kubernetes.io]  
但是，进入首页后依然会很懵逼，进入Documentation页面会更懵逼，对于初学者想依照文档搭建个环境try一下相当费劲，太乱了，下面我会整理下相关步骤以及文档地址。

### kubernetes运行环境选择 ###

官方说明：[https://kubernetes.io/docs/setup/pick-right-solution/][https_kubernetes.io_docs_setup_pick-right-solution]

> Kubernetes can run on various platforms: from your laptop, to VMs on a cloud provider, to rack of bare metal servers. The effort required to set up a cluster varies from running a single command to crafting your own customized cluster. Use this guide to choose a solution that fits your needs.

*  Local-machine Solutions  
    *just want to “kick the tires” on Kubernetes*
 *  Hosted Solutions  
    *ready to scale up to more machines and higher availability*
 *  Turnkey Cloud Solutions  
    *you already have a way to configure hosting resources*
 *  Custom Solutions

这里我们选择最简单的Local-machine Solutions模式。

我是Mac环境，会以mac为主，单操作步骤也会说明其他环境如何安装。

### 在minikube上运行Local-machine Solutions模式 ###

官网说明：[https://kubernetes.io/docs/getting-started-guides/minikube/][https_kubernetes.io_docs_getting-started-guides_minikube]

官方说明会要求你先安装minikube，安装minikube说明在  
[https://kubernetes.io/docs/tasks/tools/install-minikube/][https_kubernetes.io_docs_tasks_tools_install-minikube]，这里会要求先安装Hypervisor

### 安装Hypervisor ###

![这里写图片描述][SouthEast]

我选择的是OS X的第二个选项，VirtualBox，因为这个下载下来直接就是一个dmg文件，方便安装 VirtualBox-5.1.26-117224-OSX.dmg，94M。

安装后启动  
![这里写图片描述][SouthEast 1]  
红框内是因为我启动过本地的minikube，刚安装好时是没有的。

### 安装kubectl ###

官方说明：[https://kubernetes.io/docs/tasks/tools/install-kubectl/][https_kubernetes.io_docs_tasks_tools_install-kubectl]

![这里写图片描述][SouthEast 2]

根据环境选择不同页签哦。

我选择macos命令行输入 curl -LO [https://storage.googleapis.com/kubernetes-release/release/v1.7.0/bin/darwin/amd64/kubectl][https_storage.googleapis.com_kubernetes-release_release_v1.7.0_bin_darwin_amd64_kubectl]  
![这里写图片描述][SouthEast 3]

下载完成后，执行chmod +x ./kubectl，保证其执行权限  
![这里写图片描述][SouthEast 4]

将包移动至类路径下  
sudo mv ./kubectl /usr/local/bin/kubectl  
![这里写图片描述][SouthEast 5]

到此，kubectl就安装完成了，这页官网剩下的内容可以忽略或简单看下即可了。

### 安装Minikube ###

现在才开始真正安装Minikube

地址：[https://github.com/kubernetes/minikube/releases][https_github.com_kubernetes_minikube_releases]  
![这里写图片描述][SouthEast 6]

Windows安装包在这一页也是可以找到的，往下翻即可。

我选择OSX  
curl -Lo minikube [https://storage.googleapis.com/minikube/releases/v0.21.0/minikube-darwin-amd64][https_storage.googleapis.com_minikube_releases_v0.21.0_minikube-darwin-amd64] && chmod +x minikube && sudo mv minikube /usr/local/bin/  
![这里写图片描述][SouthEast 7]

好了，minikube安装好了，需要的安装包基本都已ok啦。

现在可以开始配置了。

### 配置 ###

依次执行如下5个步骤

![这里写图片描述][SouthEast 8]

bjjbgi-3-86:~ zhangxiaolong$ minikube start
    Starting local Kubernetes v1.7.0 cluster...
    Starting VM...
    Downloading Minikube ISO
     97.80 MB / 97.80 MB [==============================================] 100.00% 0s
    Getting VM IP address...
    Moving files into cluster...
    Setting up certs...
    Starting cluster components...
    Connecting to cluster...
    Setting up kubeconfig...
    Kubectl is now configured to use the cluster.
    bjjbgi-3-86:~ zhangxiaolong$ kubectl run hello-minikube --image=gcr.io/google_containers/echoserver:1.4 --port=8082 deployment "hello-minikube" created
    deployment "hello-minikube" created
    bjjbgi-3-86:~ zhangxiaolong$ kubectl expose deployment hello-minikube --type=NodePort
    service "hello-minikube" exposed
    bjjbgi-3-86:~ zhangxiaolong$ kubectl get pod
    NAME                              READY     STATUS              RESTARTS   AGE
    hello-minikube-2853025882-5rr1t   0/1       ContainerCreating   0          1m
    bjjbgi-3-86:~ zhangxiaolong$ curl $(minikub service hello-minikube --url)
    -bash: minikub: command not found
    curl: try 'curl --help' or 'curl --manual' for more information
    bjjbgi-3-86:~ zhangxiaolong$ curl $(minikube service hello-minikube --url)
    Waiting, endpoint for service is not ready yet...
    Waiting, endpoint for service is not ready yet...
    Waiting, endpoint for service is not ready yet...
    Waiting, endpoint for service is not ready yet...
    Waiting, endpoint for service is not ready yet...
    ^C

我的在第5步的时候，报了Waiting, endpoint for service is not ready yet.

试了几次都不行，官网上第5步成功如下图  
![这里写图片描述][SouthEast 9]

到此，我的最后一步测试没通过，明天再看吧，你们可以试试。

时间转到2017年08月02日。  
折腾了一天，算是有了点小进展，补充在这里。

昨天安装完minikube后就通过 curl $(minikube service hello-minikube –url)来测试发现 一直在waiting，其实这个hello-minikube根本没有起来。

可以通过命令kubectl get pod查看

bjjbgi-3-86:~ zhangxiaolong$ kubectl get pod
    NAME                               READY     STATUS              RESTARTS   AGE
    hello-minikube-2853025882-5rr1t    0/1       ContainerCreating   0          23h

可以看到这个服务的status是ContainerCreating，这个代表什么含义呢，表面意思是容器创建中，  
我们可以通过kubectl describe pod命令查看详细信息

bjjbgi-3-86:~ zhangxiaolong$ kubectl describe pod
    Name:       hello-minikube-2853025882-5rr1t
    Namespace:  default
    Node:       minikube/192.168.99.100
    Start Time: Tue, 01 Aug 2017 18:53:27 +0800
    Labels:     pod-template-hash=2853025882
            run=hello-minikube
    Annotations:    kubernetes.io/created-by={
       "kind":"SerializedReference","apiVersion":"v1","reference":{
       "kind":"ReplicaSet","namespace":"default","name":"hello-minikube-2853025882","uid":"a5e87f14-76a7-11e7-a070-080027... Status: Pending IP: 172.17.0.3 Created By: ReplicaSet/hello-minikube-2853025882 Controlled By: ReplicaSet/hello-minikube-2853025882 Containers: hello-minikube: Container ID: Image: gcr.io/google_containers/echoserver:1.4 Image ID: Port: 8082/TCP Args: deployment hello-minikube created State: Waiting Reason: ErrImagePull Ready: False Restart Count: 0 Environment: <none> Mounts: /var/run/secrets/kubernetes.io/serviceaccount from default-token-xxfxr (ro) Conditions: Type Status Initialized True Ready False PodScheduled True Volumes: default-token-xxfxr: Type: Secret (a volume populated by a Secret) SecretName: default-token-xxfxr Optional: false QoS Class: BestEffort Node-Selectors: <none> Tolerations: <none> Events: FirstSeen LastSeen Count From SubObjectPath Type Reason Message --------- -------- ----- ---- ------------- -------- ------ ------- 25m 25m 1 kubelet, minikube Normal SuccessfulMountVolume MountVolume.SetUp succeeded for volume "default-token-xxfxr" 23m 23m 1 kubelet, minikube spec.containers{hello-minikube} Warning Failed Failed to pull image "gcr.io/google_containers/echoserver:1.4": rpc error: code = 2 desc = Error response from daemon: {"message":"Get https://gcr.io/v1/_ping: dial tcp 64.233.189.82:443: i/o timeout"}
      22m       20m     2   kubelet, minikube   spec.containers{hello-minikube} Warning     Failed      Failed to pull image "gcr.io/google_containers/echoserver:1.4": rpc error: code = 2 desc = Error response from daemon: {
       "message":"Get https://gcr.io/v1/_ping: dial tcp 64.233.187.82:443: i/o timeout"}
      16m       16m     1   kubelet, minikube   spec.containers{hello-minikube} Warning     Failed      Failed to pull image "gcr.io/google_containers/echoserver:1.4": rpc error: code = 2 desc = Error response from daemon: {
       "message":"Get https://gcr.io/v2/google_containers/echoserver/manifests/1.4: Get https://gcr.io/v2/token?scope=repository%3Agoogle_containers%2Fechoserver%3Apull\u0026service=gcr.io: net/http: request canceled while waiting for connection (Client.Timeout exceeded while awaiting headers)"}
      19m       13m     2   kubelet, minikube   spec.containers{hello-minikube} Warning     Failed      Failed to pull image "gcr.io/google_containers/echoserver:1.4": rpc error: code = 2 desc = Error response from daemon: {
       "message":"Get https://gcr.io/v1/_ping: dial tcp 74.125.203.82:443: i/o timeout"}
      23m       8m      42  kubelet, minikube   spec.containers{hello-minikube} Normal      BackOff     Back-off pulling image "gcr.io/google_containers/echoserver:1.4"
      23m       8m      48  kubelet, minikube                   Warning     FailedSync  Error syncing pod
      25m       7m      7   kubelet, minikube   spec.containers{hello-minikube} Normal      Pulling     pulling image "gcr.io/google_containers/echoserver:1.4"
      1m        1m      1   kubelet, minikube                   Normal      SuccessfulMountVolume   MountVolume.SetUp succeeded for volume "default-token-xxfxr" 
      1m        1m      1   kubelet, minikube   spec.containers{hello-minikube} Normal      Pulling     pulling image "gcr.io/google_containers/echoserver:1.4"
      3s        3s      1   kubelet, minikube   spec.containers{hello-minikube} Warning     Failed      Failed to pull image "gcr.io/google_containers/echoserver:1.4": rpc error: code = 2 desc = Error response from daemon: {
       "message":"Get https://gcr.io/v1/_ping: dial tcp 64.233.189.82:443: i/o timeout"}
      3s        1s      2   kubelet, minikube                   Warning     FailedSync  Error syncing pod
      1s        1s      1   kubelet, minikube   spec.containers{hello-minikube} Normal      BackOff     Back-off pulling image "gcr.io/google_containers/echoserver:1.4"

相信你看到了Failed Failed to pull image “gcr.io/google\_containers/echoserver:1.4”这行信息。  
网上搜了一圈的资料，是因为gcr.io这个外国网站，我们访问不到。  
OMG！！  
所以出现了一些方案  
1 用VPN，翻墙出去  
2 使用国内镜像，推荐使用阿里云的  
可以参考[http://www.jianshu.com/p/a42eeb66a19c][http_www.jianshu.com_p_a42eeb66a19c]

minikube start kubectl run hello-minikube --image=registry.cn-hangzhou.aliyuncs.com/google-container/echoserver:1.4 --port=8080 kubectl expose deployment hello-minikube --type=NodePort kubectl get pod
    
    作者：scipio
    链接：http://www.jianshu.com/p/a42eeb66a19c
    來源：简书
    著作权归作者所有。商业转载请联系作者获得授权，非商业转载请注明出处。

3 搭建自己的docker镜像仓库，将echoserver从国内镜像中pull下来，然后推送到自己的仓库上去，然后  
minikube start kubectl run hello-minikube –image=registry.cn-hangzhou.aliyuncs.com/google-container/echoserver:1.4 –port=8080  
这一步骤替换成自己的–image。

我选择了最惨的第3条路。  
首先搭建本地docker镜像仓库，参见这里吧[http://blog.csdn.net/MrZhangXL/article/details/76598932][http_blog.csdn.net_MrZhangXL_article_details_76598932]。  
push到自己的仓库上去后，然后开始来做。

jjbgi-3-86:~ zhangxiaolong$ kubectl run hellox-minikube --image=10.20.2.127:5000/echoserver --port=8082
    deployment "hellox-minikube" created
    bjjbgi-3-86:~ zhangxiaolong$ kubectl expose deployment hellox-minikube --type=NodePort
    service "hellox-minikube" exposed
    bjjbgi-3-86:~ zhangxiaolong$ kubectl get pod
    NAME                               READY     STATUS             RESTARTS   AGE
    hellox-minikube-1229068855-2g7qv   0/1       ImagePullBackOff   0          1m

还是不行，还是ImagePullBackOff状态。  
再通过 kubectl describe pod命令看看详细信息

/var/run/secrets/kubernetes.io/serviceaccount from default-token-xxfxr (ro)
    Conditions:
      Type      Status
      Initialized   True 
      Ready     False 
      PodScheduled  True 
    Volumes:
      default-token-xxfxr:
        Type:   Secret (a volume populated by a Secret)
        SecretName: default-token-xxfxr
        Optional:   false
    QoS Class:  BestEffort
    Node-Selectors: <none>
    Tolerations:    <none>
    Events:
      FirstSeen LastSeen    Count   From            SubObjectPath               Type        Reason  Message
      --------- --------    -----   ----            -------------               --------    ------  -------
      2m        2m      1   default-scheduler                       Normal      ScheduleSuccessfully assigned hellox-minikube-1229068855-2g7qv to minikube
      2m        2m      1   kubelet, minikube                       Normal      SuccessfulMountVolume   MountVolume.SetUp succeeded for volume "default-token-xxfxr" 
      1m        1m      1   kubelet, minikube   spec.containers{hellox-minikube}    Normal      BackOff Back-off pulling image "10.20.2.127:5000/echoserver"
      2m        1m      2   kubelet, minikube   spec.containers{hellox-minikube}    Normal      Pulling pulling image "10.20.2.127:5000/echoserver"
      1m        7s      2   kubelet, minikube   spec.containers{hellox-minikube}    Warning     Failed  Failed to pull image "10.20.2.127:5000/echoserver": rpc error: code = 2 desc = Error response from daemon: {
       "message":"Get https://10.20.2.127:5000/v1/_ping: http: server gave HTTP response to HTTPS client"}
      1m        7s      3   kubelet, minikube                       Warning     FailedSync      Error syncing pod

仿佛换了个错误，http: server gave HTTP response to HTTPS client，这个错误原因是因为给了https请求的http响应，应该改我镜像仓库机器没有配置https证书。  
搜索解决方案是：  
启动minikube时增加参数–insecure-registry

jjbgi-3-86:~ zhangxiaolong$ minikube delete
    Deleting local Kubernetes cluster...
    Machine deleted.
    bjjbgi-3-86:~ zhangxiaolong$ minikube start --vm-driver=virtualbox --insecure-registry=10.20.2.127:5000
    Starting local Kubernetes v1.7.0 cluster...
    Starting VM...
    Getting VM IP address...
    Moving files into cluster...
    Setting up certs...
    Starting cluster components...
    Connecting to cluster...
    Setting up kubeconfig...

接着启服务

jjbgi-3-86:~ zhangxiaolong$ kubectl run hellox-minikube --image=10.20.2.127:5000/echoserver --port=8082
    deployment "hellox-minikube" created
    bjjbgi-3-86:~ zhangxiaolong$ kubectl expose deployment hellox-minikube --type=NodePort
    service "hellox-minikube" exposed
    bjjbgi-3-86:~ zhangxiaolong$ kubectl get pods
    NAME                               READY     STATUS              RESTARTS   AGE
    hellox-minikube-1229068855-p5ls6   0/1       ContainerCreating   0          55s

还是ContainerCreating状态，要崩溃了。

继续kubectl describe hellox-minikube-1229068855-p5ls6命令看看详细信息

State:       Waiting
          Reason:       ContainerCreating
        Ready:      False
        Restart Count:  0
        Environment:    <none>
        Mounts:
          /var/run/secrets/kubernetes.io/serviceaccount from default-token-gxqn0 (ro)
    Conditions:
      Type      Status
      Initialized   True 
      Ready     False 
      PodScheduled  True 
    Volumes:
      default-token-gxqn0:
        Type:   Secret (a volume populated by a Secret)
        SecretName: default-token-gxqn0
        Optional:   false
    QoS Class:  BestEffort
    Node-Selectors: <none>
    Tolerations:    <none>
    Events:
      FirstSeen LastSeen    Count   From            SubObjectPath   Type        Reason          Message
      --------- --------    -----   ----            -------------   --------    ------          -------
      1m        1m      1   default-scheduler           Normal      Scheduled       Successfully assigned hellox-minikube-1229068855-p5ls6 to minikube
      1m        1m      1   kubelet, minikube           Normal      SuccessfulMountVolume   MountVolume.SetUp succeeded for volume "default-token-gxqn0" 
      49s       49s     1   kubelet, minikube           Warning     FailedSync      Error syncing pod

好像并没有什么错误啊，只有这个Error syncing pod

网上搜了一圈，也没有答案，最后还是在[http://www.jianshu.com/p/a42eeb66a19c][http_www.jianshu.com_p_a42eeb66a19c]这篇文章中看到了一些猫腻

他的报错信息，是这样子的

Events: FirstSeen LastSeen Count From SubobjectPath  Type Reason Message --------- -------- ----- ---- ------------- -------- ------ ------- 8m 8m 1 {default-scheduler } Normal Scheduled Successfully assigned hello-minikube-957602326-t9mzf to minikube 6m 3m 2 {kubelet minikube} Warning FailedSync Error syncing pod, skipping: failed to "StartContainer" for "POD" with ErrImagePull: "image pull failed for gcr.io/google_containers/pause-amd64:3.0, this may be because there are no credentials on this request. details: (Error response from daemon: Get https://gcr.io/v1/_ping: dial tcp 64.233.187.82:443: i/o timeout)" 6m 1m 10 {kubelet minikube} Warning FailedSync Error syncing pod, skipping: failed to "StartContainer" for "POD" with ImagePullBackOff: "Back-off pulling image \"gcr.io/google_containers/pause-amd64:3.0\""
    
    作者：scipio
    链接：http://www.jianshu.com/p/a42eeb66a19c
    來源：简书
    著作权归作者所有。商业转载请联系作者获得授权，非商业转载请注明出处。

他有details，这太完美了，难道我的是没有details，原因和其一样么？  
抱着试试看的心态，使用了他的解决方案：

minikube ssh docker pull registry.cn-hangzhou.aliyuncs.com/google-containers/pause-amd64:3.0 docker tag registry.cn-hangzhou.aliyuncs.com/google-containers/pause-amd64:3.0 gcr.io/google_containers/pause-amd64:3.0
    
    作者：scipio
    链接：http://www.jianshu.com/p/a42eeb66a19c
    來源：简书
    著作权归作者所有。商业转载请联系作者获得授权，非商业转载请注明出处。

执行完毕后 通过exit命令退出ssh交互。  
此时，再看看pod状态

bjjbgi-3-86:~ zhangxiaolong$ kubectl get pod
    NAME                               READY     STATUS             RESTARTS   AGE
    hellox-minikube-1229068855-7j2n2   1/1       Running            1          30m

居然运行起来了，哈哈哈哈哈。。。

bjjbgi-3-86:~ zhangxiaolong$ minikube dashboard
    Opening kubernetes dashboard in default browser...

![这里写图片描述][SouthEast 10]

[https_kubernetes.io]: https://kubernetes.io/
[https_kubernetes.io_docs_setup_pick-right-solution]: https://kubernetes.io/docs/setup/pick-right-solution/
[https_kubernetes.io_docs_getting-started-guides_minikube]: https://kubernetes.io/docs/getting-started-guides/minikube/
[https_kubernetes.io_docs_tasks_tools_install-minikube]: https://kubernetes.io/docs/tasks/tools/install-minikube/
[SouthEast]: /images/20220611/c7e1a86e18904e6d95161904c5cae2e6.png
[SouthEast 1]: /images/20220611/4f81cc30e4594884a016c040a3fe4f4f.png
[https_kubernetes.io_docs_tasks_tools_install-kubectl]: https://kubernetes.io/docs/tasks/tools/install-kubectl/
[SouthEast 2]: /images/20220611/c0c3b9c371424e4f8f21552a43b5a871.png
[https_storage.googleapis.com_kubernetes-release_release_v1.7.0_bin_darwin_amd64_kubectl]: https://storage.googleapis.com/kubernetes-release/release/v1.7.0/bin/darwin/amd64/kubectl
[SouthEast 3]: /images/20220611/7ae589cc952e48608bd15b0342456c21.png
[SouthEast 4]: /images/20220611/b016a9084ccb4dd7a953558497171be9.png
[SouthEast 5]: /images/20220611/6f66c1ad42bb4765ab758803070ac440.png
[https_github.com_kubernetes_minikube_releases]: https://github.com/kubernetes/minikube/releases
[SouthEast 6]: /images/20220611/6bb1c48334584763b0e5133f088bcdb4.png
[https_storage.googleapis.com_minikube_releases_v0.21.0_minikube-darwin-amd64]: https://storage.googleapis.com/minikube/releases/v0.21.0/minikube-darwin-amd64
[SouthEast 7]: /images/20220611/0da3a7e2f8e840c48f024795e55c01c6.png
[SouthEast 8]: /images/20220611/abb6296c46914a42a36c427a0e0721e1.png
[SouthEast 9]: /images/20220611/bcfb8e796f8141cdb979b9f036b26cf6.png
[http_www.jianshu.com_p_a42eeb66a19c]: http://www.jianshu.com/p/a42eeb66a19c
[http_blog.csdn.net_MrZhangXL_article_details_76598932]: http://blog.csdn.net/MrZhangXL/article/details/76598932
[SouthEast 10]: /images/20220611/1753d437f0c34b0fbe6861065e2c2909.png