Kubernetes 部署Dashboard UI

实践环境

CentOS-7-x86_64-DVD-1810

Docker 19.03.9

Kubernetes version: v1.20.5

发布Dashboard

可以通过运行以下命令部署Dashboard

kubectl apply -f https://raw.githubusercontent.com/kubernetes/dashboard/v2.0.0/aio/deploy/recommended.yaml

实践如下

# kubectl apply -f https://raw.githubusercontent.com/kubernetes/dashboard/v2.0.0/aio/deploy/recommended.yaml
namespace/kubernetes-dashboard created
serviceaccount/kubernetes-dashboard created
service/kubernetes-dashboard created
secret/kubernetes-dashboard-certs created
secret/kubernetes-dashboard-csrf created
secret/kubernetes-dashboard-key-holder created
configmap/kubernetes-dashboard-settings created
role.rbac.authorization.k8s.io/kubernetes-dashboard created
clusterrole.rbac.authorization.k8s.io/kubernetes-dashboard created
rolebinding.rbac.authorization.k8s.io/kubernetes-dashboard created
clusterrolebinding.rbac.authorization.k8s.io/kubernetes-dashboard created
deployment.apps/kubernetes-dashboard created
service/dashboard-metrics-scraper created
deployment.apps/dashboard-metrics-scraper created

访问Dashboard UI

为了保护你的集群数据，默认情况下，Dashboard 会使用最少的 RBAC 配置进行部署。 当前，Dashboard 仅支持使用 Bearer 令牌登录。

为演示样本创建登录Token

当前目录下新建 dashboard-adminuser.yaml（文件名称可自定义，执行命令时指定正确填写对应文件名称即可，下同不再赘述），内容如下

apiVersion: v1
kind: ServiceAccount
metadata:
  name: admin-user
  namespace: kubernetes-dashboard

运行以下命令，根据上述配置文件创建名为admin-user，归属名称空间为kubernetes-dashboard的服务帐号

# kubectl apply -f dashboard-adminuser.yaml
serviceaccount/admin-user created

新建 dashboard-cluster-role-binding.yaml，内容如下

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

备注：多数情况下，使用kops、kubeadm、或其它流行工具配置好集群后，ClusterRole cluster-admin自动创建了。如果不存在，需要先手工创建，并授予必要权限。

运行以下命令，根据上述配置文件为服务账号创建ClusterRoleBinding。

# kubectl apply -f dashboard-cluster-role-binding.yaml
clusterrolebinding.rbac.authorization.k8s.io/admin-user created

运行以下命令获取Bear Token

# kubectl -n kubernetes-dashboard get secret $(kubectl -n kubernetes-dashboard get sa/admin-user -o jsonpath="{.secrets[0].name}") -o go-template="{{.data.token | base64decode}}"
eyJhbGciOiJSUzI1NiIsImtpZCI6ImhmajhXejRnVlFaR1huTnhESGZlQlpVQlZiQ0JqbG5UU19CS05TQktnV3MifQ.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.JXtlllOrXidMnUTOJt2Z8jkQctULLn0rlb0FwpTfjwcmZm9VknpYjUiek3C_1ddeptt6XanIwXQV58ZHNZ5qgImutZ1Tt9u5Nn25pFWNvcUsyeh_HSrebfOJUBQzj7c_3gC1VKQMSEiR8_d6b8dJBdtaYoQdhwyNciHqFkWyLkCZ5jD7DjOSQfFAQgqIf5ozLxFQiJXabCjagEnCO7nF2esGvlZLu1WiuE0TgR5cDFi2bLln7CTbSB75J96SEyrBsTG9-fp7ay5dH84do94obKo3zn-L1-GySMoj_2tPHcnCajXTpovdylot4wieHpvU26Ss1DsdkMvl8jVf9kO4pg[root@localhost ~]#

参考连接

https://github.com/kubernetes/dashboard/blob/master/docs/user/access-control/creating-sample-user.md

命令行代理

可以使用kubectl命令行工具访问Dashboard，如下：

# kubectl proxy

上述命令执行成功后，可通过以下链接访问Dashboard，不过需要特别注意的是，该链接仅支持从运行上述命令的机器进行访问，即不可远程访问。

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

实践时，笔者尝试增加参数运行上述命令，如下，这样虽然可以解决不能远程访问的问题，但是依旧存在问题：点击登录，不跳转。

# kubectl proxy --address=10.118.80.93 --accept-hosts='^*$'

注意：如果不加 --accept-hosts，访问上述链接时，会提示 Forbidden

最终解决方案如下：

1、在安装了dashboard的结点机上运行以下命令

# kubectl port-forward --namespace kubernetes-dashboard --address 0.0.0.0 service/kubernetes-dashboard 443
Forwarding from 0.0.0.0:443 -> 8443
Handling connection for 443
Handling connection for 443

2、通过https://node_ip链接进行访问，其中node_ip为上述结点机的ip地址，如下

输入上述获取的Token，点击登录，完成

注意：Token有效时间为24小时，过期需要重新生成。

清理

运行以下命令，移除用于演示的管理员服务帐号和ClusterRoleBinding

# kubectl -n kubernetes-dashboard delete serviceaccount admin-user
# kubectl -n kubernetes-dashboard delete clusterrolebinding admin-user

参考连接

https://kubernetes.io/zh/docs/tasks/access-application-cluster/web-ui-dashboard/

https://github.com/kubernetes/dashboard/blob/master/docs/user/accessing-dashboard/README.md

https://github.com/kubernetes/dashboard/tree/master/docs