kubernetes 初体验-mac版

之前在mac上体验kubernetes要使用minikube，最近发现Docker-Desktop自带的k8s更方便，简单记录一下安装过程。

docker-desktop安装及kubernetes启用

如果没有安装docker-desktop，可以先去 https://www.docker.com/products/docker-desktop 下载和安装。如果已经安装过，请升级到新的版本。我的docker版本是:

docker-version

然后在Docker-Engine里配置一下国内镜像，这样kubernetes启用会迅速一些:

{
  "debug": true,
  "registry-mirrors": [
    "https://hub-mirror.c.163.com",
    "https://mirror.baidubce.com"
  ],
  "builder": {
    "gc": {
      "defaultKeepStorage": "20GB",
      "enabled": true
    }
  },
  "experimental": false
}

配置镜像后，可以使用下面命令检查一下:

# docker info
...
 Registry Mirrors:
  https://hub-mirror.c.163.com/
  https://mirror.baidubce.com/

然后在图形界面上启用kubernets：

kubernetes

完成后使用kubectl命令检查一下版本:

# kubectl version
Client Version: version.Info{Major:"1", Minor:"19", GitVersion:"v1.19.7", GitCommit:"1dd5338295409edcfff11505e7bb246f0d325d15", GitTreeState:"clean", BuildDate:"2021-01-13T13:23:52Z", GoVersion:"go1.15.5", Compiler:"gc", Platform:"darwin/amd64"}
Server Version: version.Info{Major:"1", Minor:"19", GitVersion:"v1.19.7", GitCommit:"1dd5338295409edcfff11505e7bb246f0d325d15", GitTreeState:"clean", BuildDate:"2021-01-13T13:15:20Z", GoVersion:"go1.15.5", Compiler:"gc", Platform:"linux/amd64"}

查看唯一的master节点:

# kubectl get node
NAME             STATUS   ROLES    AGE   VERSION
docker-desktop   Ready    master   18h   v1.19.7

查看默认的名称空间:

# kubectl get ns(namespace)
NAME                   STATUS   AGE
default                Active   18h
kube-node-lease        Active   18h
kube-public            Active   18h
kube-system            Active   18h

查看默认的pods:

kubectl get pods --all-namespaces
NAMESPACE              NAME                                         READY   STATUS    RESTARTS   AGE
kube-system            coredns-f9fd979d6-76f9t                      1/1     Running   1          18h
kube-system            coredns-f9fd979d6-dm469                      1/1     Running   1          18h
kube-system            etcd-docker-desktop                          1/1     Running   1          18h
kube-system            kube-apiserver-docker-desktop                1/1     Running   1          18h
kube-system            kube-controller-manager-docker-desktop       1/1     Running   1          18h
kube-system            kube-proxy-xvv2f                             1/1     Running   1          18h
kube-system            kube-scheduler-docker-desktop                1/1     Running   1          18h
kube-system            storage-provisioner                          1/1     Running   2          18h
kube-system            vpnkit-controller        

接下来，我们安装kubernetes-dashboard。安装后可以图形化的管理/查看kubernetes的内部状态，非常方便，同时也可以验证搭建的kubernetes可以正常工作。

kubernetes-dashboard 的安装

首先下载kubernetes-dashboard的yaml文件:

curl -LO https://raw.githubusercontent.com/kubernetes/dashboard/v2.3.1/aio/deploy/recommended.yaml

使用apply子指令安装 kubectl apply -f recommended.yaml

所有yaml文件的启用都使用 kubectl apply

创建rbac权限的配置文件 kubernetes-dashboard-admin.yaml ，然后启用。

apiVersion: v1
kind: ServiceAccount
metadata:
  name: kubernetes-dashboard-admin
  namespace: kubernetes-dashboard
  labels:
    k8s-app: kubernetes-dashboard
---
apiVersion: rbac.authorization.k8s.io/v1
kind: ClusterRoleBinding
metadata:
  name: kubernetes-dashboard-admin
  namespace: kubernetes-dashboard
roleRef:
  apiGroup: rbac.authorization.k8s.io
  kind: ClusterRole
  name: cluster-admin
subjects:
- kind: ServiceAccount
  name: kubernetes-dashboard-admin
  namespace: kubernetes-dashboard

命令正常执行就可以完成kubernetes-dashboard的安装。

使用proxy访问kubernetes-dashboard

我们先使用下面的命令，在本地8001端口代理kubernetes的内部服务:

kubectl proxy

然后使用浏览器访问下面的网页链接:

http://localhost:8001/api/v1/namespaces/kubernetes-dashboard/services/https:kubernetes-dashboard:/proxy/.

这时候页面会提示需要输入token。可以使用下面命令查看admin的token:

kubectl -n kubernetes-dashboard describe secret $(kubectl -n kubernetes-dashboard get secret | grep kubernetes-dashboard-admin | awk '{print $1}')

登录后就可以看到kubernetes的所有信息, 如图:

dashboard

使用NodePort访问kubernetes-dashboard

使用proxy方式访问，需要先启动proxy服务，不太方便。我们可以更改kubernetes-dashboard服务为NodePort方式，这样可以直接使用ip+port方式访问。修改recommended.yaml的下面部分内容:

kind: Service # 服务
apiVersion: v1
metadata:
  labels:
    k8s-app: kubernetes-dashboard
  name: kubernetes-dashboard # 名称
  namespace: kubernetes-dashboard
spec:
  type: NodePort # 增加这一行
  ports:
    - port: 443
      targetPort: 8443

然后使用kubectl apply更新dashboard，完成后检查本地端口:

kubectl get svc -n kubernetes-dashboard
NAME                        TYPE        CLUSTER-IP       EXTERNAL-IP   PORT(S)         AGE
dashboard-metrics-scraper   ClusterIP   10.108.2.0       <none>        8000/TCP        106d
kubernetes-dashboard        NodePort    10.110.204.165   <none>        443:32072/TCP   106d

使用firefox访问 https://127.0.0.1:32072/，这里的 32072 是使用NodePort方式部署的随机端口映射。

因为https的证书安全问题，chrome和safari都无法访问。

使用ingress访问kubernetes-dashboard

NodePort方式访问dashboard会有安全证书问题，单机最合适的方式还是部署ingress。先从下面路径下载nginx实现的ingress并安装:

curl -L  https://raw.githubusercontent.com/kubernetes/ingress-nginx/controller-v0.46.0/deploy/static/provider/cloud/deploy.yaml -o ingress-nginx.yaml

检查安装后的pod，ingress-nginx-controller需要是running状态表示安装完成:

kubectl get pods --all-namespaces
NAMESPACE              NAME                                         READY   STATUS      RESTARTS   AGE
ingress-nginx          ingress-nginx-admission-create-p5znr         0/1     Completed   0          17h
ingress-nginx          ingress-nginx-admission-patch-t9447          0/1     Completed   0          17h
ingress-nginx          ingress-nginx-controller-57cb5bf694-wc6tv    1/1     Running     0          17h

查看ingress-nginx服务的端口，这里https是31212:

kubectl get svc --all-namespaces
NAMESPACE              NAME                                 TYPE        CLUSTER-IP       EXTERNAL-IP   PORT(S)                                     AGE
default                kubernetes                           ClusterIP   10.96.0.1        <none>        443/TCP                                     106d
ingress-nginx          ingress-nginx-controller             NodePort    10.105.160.62    <none>        80:30303/TCP,443:31212/TCP,9000:30835/TCP   80m
ingress-nginx          ingress-nginx-controller-admission   ClusterIP   10.102.194.29    <none>        443/TCP                                     80m
kube-system            kube-dns                             ClusterIP   10.96.0.10       <none>        53/UDP,53/TCP,9153/TCP                      106d
kubernetes-dashboard   dashboard-metrics-scraper            ClusterIP   10.108.107.121   <none>        8000/TCP                                    44m

编写我们自定义的ingress dashboard-ingress.yaml:

apiVersion: networking.k8s.io/v1
kind: Ingress
metadata:
  name: dashboard-ingress
  namespace: kubernetes-dashboard
  annotations:
    kubernetes.io/ingress.class: 'nginx'
    nginx.ingress.kubernetes.io/ssl-passthrough: 'true'
    nginx.ingress.kubernetes.io/backend-protocol: 'HTTPS'
spec:
  rules:
    - host: 'my-dashboard.com'
      http:
        paths:
          - pathType: Prefix
            path: '/'
            backend:
              service:
                name: kubernetes-dashboard
                port:
                  number: 443

检查ing配置生效:

kubectl get ing --all-namespaces
Warning: extensions/v1beta1 Ingress is deprecated in v1.14+, unavailable in v1.22+; use networking.k8s.io/v1 Ingress
NAMESPACE              NAME                CLASS    HOSTS              ADDRESS     PORTS   AGE
kubernetes-dashboard   dashboard-ingress   <none>   my-dashboard.com   localhost   80      17h

在访问前，需要修改一下本地 /etc/hosts 文件把my-dashboard.com指向本地ip。然后使用浏览器访问下面地址：

https://my-dashboard.com:31212/

注意必须使用https访问。如果有其它问题可以看这里:https://github.com/kubernetes/dashboard/blob/master/docs/user/accessing-dashboard/README.md#login-not-available

小结

我们启用mac上docker-desktop自带的kubernetes，安装kubernetes-dashboard用来进行图形化管理。同时介绍了使用proxy，NodePort和Ingress三种方式访问dashboard。

参考链接

• 在MacOS上搭建Kubernetes https://xiangflight.github.io/build-kubernetes-on-mac-os/
• 镜像加速器 https://yeasy.gitbook.io/docker_practice/install/mirror
• docker-desktop下载 https://www.docker.com/products/docker-desktop
• kubernetes文档 https://kubernetes.io/docs/tasks/access-application-cluster/web-ui-dashboard/

本文由哈喽比特于3年以前收录，如有侵权请联系我们。
文章来源：https://mp.weixin.qq.com/s/h5Zf659HPkD3MOSAu_op5A