Kubernetes学习之路（十九）之Kubernetes dashboard认证访问

Dashboard:https://github.com/kubernetes/dashboard

一、Dashboard部署

由于需要用到k8s.gcr.io/kubernetes-dashboard-amd64:v1.10.0，这里有2种方式进行pull 镜像。docker search该镜像名称，直接pull，再重新进行tag；另外一种方式是通过谷歌容器镜像拉取。

[root@k8s-node01 ~]# docker pull siriuszg/kubernetes-dashboard-amd64  
[root@k8s-node01 ~]# docker tag siriuszg/kubernetes-dashboard-amd64:latest k8s.gcr.io/kubernetes-dashboard-amd64:v1.10.0

或者是
[root@k8s-node01 ~]# docker pull mirrorgooglecontainers/kubernetes-dashboard-amd64:v1.10.0

再看其部署的过程：

[root@k8s-master ~]# kubectl apply -f https://raw.githubusercontent.com/kubernetes/dashboard/master/src/deploy/recommended/kubernetes-dashboard.yaml
secret/kubernetes-dashboard-certs created
serviceaccount/kubernetes-dashboard created
role.rbac.authorization.k8s.io/kubernetes-dashboard-minimal created
rolebinding.rbac.authorization.k8s.io/kubernetes-dashboard-minimal created
deployment.apps/kubernetes-dashboard created
service/kubernetes-dashboard created

[root@k8s-master ~]# kubectl get pods -n kube-system
NAME                                   READY     STATUS    RESTARTS   AGE
coredns-78fcdf6894-nmcmz               1/1       Running   1          54d
coredns-78fcdf6894-p5pfm               1/1       Running   1          54d
etcd-k8s-master                        1/1       Running   2          54d
kube-apiserver-k8s-master              1/1       Running   9          54d
kube-controller-manager-k8s-master     1/1       Running   5          54d
kube-flannel-ds-n5c86                  1/1       Running   1          54d
kube-flannel-ds-nrcw2                  1/1       Running   1          52d
kube-flannel-ds-pgpr7                  1/1       Running   5          54d
kube-proxy-glzth                       1/1       Running   1          52d
kube-proxy-rxlt7                       1/1       Running   2          54d
kube-proxy-vxckf                       1/1       Running   4          54d
kube-scheduler-k8s-master              1/1       Running   3          54d
kubernetes-dashboard-767dc7d4d-n4clq   1/1       Running   0          3s

[root@k8s-master ~]# kubectl get svc -n kube-system
NAME                   TYPE        CLUSTER-IP     EXTERNAL-IP   PORT(S)         AGE
kube-dns               ClusterIP   10.96.0.10     <none>        53/UDP,53/TCP   54d
kubernetes-dashboard   ClusterIP   10.105.204.4   <none>        443/TCP         30m

[root@k8s-master ~]# kubectl patch svc kubernetes-dashboard -p '{"spec":{"type":"NodePort"}}' -n kube-system  #以打补丁方式修改dasboard的访问方式
service/kubernetes-dashboard patched
[root@k8s-master ~]# kubectl get svc -n kube-system
NAME                   TYPE        CLUSTER-IP     EXTERNAL-IP   PORT(S)         AGE
kube-dns               ClusterIP   10.96.0.10     <none>        53/UDP,53/TCP   54d
kubernetes-dashboard   NodePort    10.105.204.4   <none>        443:32645/TCP   31m

浏览器访问：https://192.168.56.12:32645，如图：这里需要注意的是谷歌浏览器会禁止不安全证书访问，建议使用火狐浏览器，并且需要在高级选项中添加信任

在k8s中 dashboard可以有两种访问方式：kubeconfig（HTTPS）和token（http）

1、token认证

 （1）创建dashboard专用证书

[root@k8s-master pki]# (umask 077;openssl genrsa -out dashboard.key 2048)
Generating RSA private key, 2048 bit long modulus
.....................................................................................................+++
..........................+++
e is 65537 (0x10001)

（2）证书签署请求

[root@k8s-master pki]# openssl req -new -key dashboard.key -out dashboard.csr -subj "/O=magedu/CN=dashboard"
[root@k8s-master pki]# openssl x509 -req -in dashboard.csr -CA ca.crt -CAkey ca.key -CAcreateserial -out dashboard.crt -days 365
Signature ok
subject=/O=magedu/CN=dashboard
Getting CA Private Key

（3）定义令牌方式仅能访问default名称空间

[root@k8s-master pki]# kubectl create secret generic dashboard-cert -n kube-system --from-file=./dashboard.crt --from-file=dashboard.key=./dashboard.key   #secret创建
secret/dashboard-cert created

[root@k8s-master pki]# kubectl get secret -n kube-system |grep dashboard
dashboard-cert                                   Opaque                                2         1m
kubernetes-dashboard-certs                       Opaque                                0         3h
kubernetes-dashboard-key-holder                  Opaque                                2         3h
kubernetes-dashboard-token-jpbgw                 kubernetes.io/service-account-token   3         3h

[root@k8s-master pki]# kubectl create serviceaccount def-ns-admin -n default  #创建serviceaccount
serviceaccount/def-ns-admin created

[root@k8s-master pki]# kubectl create rolebinding def-ns-admin --clusterrole=admin --serviceaccount=default:def-ns-admin  #service account账户绑定到集群角色admin
rolebinding.rbac.authorization.k8s.io/def-ns-admin created

[root@k8s-master pki]# kubectl describe secret def-ns-admin-token-k9fz9  #查看def-ns-admin这个serviceaccount的token
Name:         def-ns-admin-token-k9fz9
Namespace:    default
Labels:       <none>
Annotations:  kubernetes.io/service-account.name=def-ns-admin
              kubernetes.io/service-account.uid=56ed901c-d042-11e8-801a-000c2972dc1f

Type:  kubernetes.io/service-account-token

Data
====
ca.crt:     1025 bytes
namespace:  7 bytes
token:      eyJhbGciOiJSUzI1NiIsImtpZCI6IiJ9.eyJpc3MiOiJrdWJlcm5ldGVzL3NlcnZpY2VhY2NvdW50Iiwia3ViZXJuZXRlcy5pby9zZXJ2aWNlYWNjb3VudC9uYW1lc3BhY2UiOiJkZWZhdWx0Iiwia3ViZXJuZXRlcy5pby9zZXJ2aWNlYWNjb3VudC9zZWNyZXQubmFtZSI6ImRlZi1ucy1hZG1pbi10b2tlbi1rOWZ6OSIsImt1YmVybmV0ZXMuaW8vc2VydmljZWFjY291bnQvc2VydmljZS1hY2NvdW50Lm5hbWUiOiJkZWYtbnMtYWRtaW4iLCJrdWJlcm5ldGVzLmlvL3NlcnZpY2VhY2NvdW50L3NlcnZpY2UtYWNjb3VudC51aWQiOiI1NmVkOTAxYy1kMDQyLTExZTgtODAxYS0wMDBjMjk3MmRjMWYiLCJzdWIiOiJzeXN0ZW06c2VydmljZWFjY291bnQ6ZGVmYXVsdDpkZWYtbnMtYWRtaW4ifQ.QfB5RR19nBv4-kFYyzW5-2n5Ksg-kON8lU18-COLBNfObQTDHs926m4k9f_5bto4YGncYi7sV_3oEec8ouW1FRjJWfY677L1IqIlwcuqc-g0DUo21zkjY_s3Lv3JSb_AfXUbZ7VTeWOhvwonqfK8uriGO1-XET-RBk1CE4Go1sL7X5qDgPjNO1g85D9IbIZG64VygplT6yZNc-b7tLNn_O49STthy6J0jdNk8lYxjy6UJohoTicy2XkZMHp8bNPBj9RqGqMSnnJxny5WO3vHxYAodKx7h6w-PtuON84lICnhiJ06RzsWjZfdeaQYg4gCZmd2J6Hdq0_K32n3l3kFLg

将该token复制后，填入验证，要知道的是，该token认证仅可以查看default名称空间的内容，如下图：

 2、kubeconfig认证 

（1）配置def-ns-admin的集群信息

[root@k8s-master pki]# kubectl config set-cluster kubernetes --certificate-authority=./ca.crt --server="https://192.168.56.11:6443" --embed-certs=true --kubeconfig=/root/def-ns-admin.conf
Cluster "kubernetes" set.

（2）使用token写入集群验证

[root@k8s-master ~]# kubectl config set-credentials -h  #认证的方式可以通过crt和key文件，也可以使用token进行配置，这里使用tonken

Usage:
  kubectl config set-credentials NAME [--client-certificate=path/to/certfile] [--client-key=path/to/keyfile]
[--token=bearer_token] [--username=basic_user] [--password=basic_password] [--auth-provider=provider_name]
[--auth-provider-arg=key=value] [options]

[root@k8s-master pki]# kubectl describe secret def-ns-admin-token-k9fz9
Name:         def-ns-admin-token-k9fz9
Namespace:    default
Labels:       <none>
Annotations:  kubernetes.io/service-account.name=def-ns-admin
              kubernetes.io/service-account.uid=56ed901c-d042-11e8-801a-000c2972dc1f

Type:  kubernetes.io/service-account-token

Data
====
ca.crt:     1025 bytes
namespace:  7 bytes
token:      eyJhbGciOiJSUzI1NiIsImtpZCI6IiJ9.eyJpc3MiOiJrdWJlcm5ldGVzL3NlcnZpY2VhY2NvdW50Iiwia3ViZXJuZXRlcy5pby9zZXJ2aWNlYWNjb3VudC9uYW1lc3BhY2UiOiJkZWZhdWx0Iiwia3ViZXJuZXRlcy5pby9zZXJ2aWNlYWNjb3VudC9zZWNyZXQubmFtZSI6ImRlZi1ucy1hZG1pbi10b2tlbi1rOWZ6OSIsImt1YmVybmV0ZXMuaW8vc2VydmljZWFjY291bnQvc2VydmljZS1hY2NvdW50Lm5hbWUiOiJkZWYtbnMtYWRtaW4iLCJrdWJlcm5ldGVzLmlvL3NlcnZpY2VhY2NvdW50L3NlcnZpY2UtYWNjb3VudC51aWQiOiI1NmVkOTAxYy1kMDQyLTExZTgtODAxYS0wMDBjMjk3MmRjMWYiLCJzdWIiOiJzeXN0ZW06c2VydmljZWFjY291bnQ6ZGVmYXVsdDpkZWYtbnMtYWRtaW4ifQ.QfB5RR19nBv4-kFYyzW5-2n5Ksg-kON8lU18-COLBNfObQTDHs926m4k9f_5bto4YGncYi7sV_3oEec8ouW1FRjJWfY677L1IqIlwcuqc-g0DUo21zkjY_s3Lv3JSb_AfXUbZ7VTeWOhvwonqfK8uriGO1-XET-RBk1CE4Go1sL7X5qDgPjNO1g85D9IbIZG64VygplT6yZNc-b7tLNn_O49STthy6J0jdNk8lYxjy6UJohoTicy2XkZMHp8bNPBj9RqGqMSnnJxny5WO3vHxYAodKx7h6w-PtuON84lICnhiJ06RzsWjZfdeaQYg4gCZmd2J6Hdq0_K32n3l3kFLg

这里的token是base64编码，此处需要进行解码操作
[root@k8s-master ~]# kubectl get secret def-ns-admin-token-k9fz9 -o jsonpath={.data.token} |base64 -d
eyJhbGciOiJSUzI1NiIsImtpZCI6IiJ9.eyJpc3MiOiJrdWJlcm5ldGVzL3NlcnZpY2VhY2NvdW50Iiwia3ViZXJuZXRlcy5pby9zZXJ2aWNlYWNjb3VudC9uYW1lc3BhY2UiOiJkZWZhdWx0Iiwia3ViZXJuZXRlcy5pby9zZXJ2aWNlYWNjb3VudC9zZWNyZXQubmFtZSI6ImRlZi1ucy1hZG1pbi10b2tlbi1rOWZ6OSIsImt1YmVybmV0ZXMuaW8vc2VydmljZWFjY291bnQvc2VydmljZS1hY2NvdW50Lm5hbWUiOiJkZWYtbnMtYWRtaW4iLCJrdWJlcm5ldGVzLmlvL3NlcnZpY2VhY2NvdW50L3NlcnZpY2UtYWNjb3VudC51aWQiOiI1NmVkOTAxYy1kMDQyLTExZTgtODAxYS0wMDBjMjk3MmRjMWYiLCJzdWIiOiJzeXN0ZW06c2VydmljZWFjY291bnQ6ZGVmYXVsdDpkZWYtbnMtYWRtaW4ifQ.QfB5RR19nBv4-kFYyzW5-2n5Ksg-kON8lU18-COLBNfObQTDHs926m4k9f_5bto4YGncYi7sV_3oEec8ouW1FRjJWfY677L1IqIlwcuqc-g0DUo21zkjY_s3Lv3JSb_AfXUbZ7VTeWOhvwonqfK8uriGO1-XET-RBk1CE4Go1sL7X5qDgPjNO1g85D9IbIZG64VygplT6yZNc-b7tLNn_O49STthy6J0jdNk8lYxjy6UJohoTicy2XkZMHp8bNPBj9RqGqMSnnJxny5WO3vHxYAodKx7h6w-PtuON84lICnhiJ06RzsWjZfdeaQYg4gCZmd2J6Hdq0_K32n3l3kFLg

配置token信息
[root@k8s-master ~]# kubectl config set-credentials def-ns-admin --token=eyJhbGciOiJSUzI1NiIsImtpZCI6IiJ9.eyJpc3MiOiJrdWJlcm5ldGVzL3NlcnZpY2VhY2NvdW50Iiwia3ViZXJuZXRlcy5pby9zZXJ2aWNlYWNjb3VudC9uYW1lc3BhY2UiOiJkZWZhdWx0Iiwia3ViZXJuZXRlcy5pby9zZXJ2aWNlYWNjb3VudC9zZWNyZXQubmFtZSI6ImRlZi1ucy1hZG1pbi10b2tlbi1rOWZ6OSIsImt1YmVybmV0ZXMuaW8vc2VydmljZWFjY291bnQvc2VydmljZS1hY2NvdW50Lm5hbWUiOiJkZWYtbnMtYWRtaW4iLCJrdWJlcm5ldGVzLmlvL3NlcnZpY2VhY2NvdW50L3NlcnZpY2UtYWNjb3VudC51aWQiOiI1NmVkOTAxYy1kMDQyLTExZTgtODAxYS0wMDBjMjk3MmRjMWYiLCJzdWIiOiJzeXN0ZW06c2VydmljZWFjY291bnQ6ZGVmYXVsdDpkZWYtbnMtYWRtaW4ifQ.QfB5RR19nBv4-kFYyzW5-2n5Ksg-kON8lU18-COLBNfObQTDHs926m4k9f_5bto4YGncYi7sV_3oEec8ouW1FRjJWfY677L1IqIlwcuqc-g0DUo21zkjY_s3Lv3JSb_AfXUbZ7VTeWOhvwonqfK8uriGO1-XET-RBk1CE4Go1sL7X5qDgPjNO1g85D9IbIZG64VygplT6yZNc-b7tLNn_O49STthy6J0jdNk8lYxjy6UJohoTicy2XkZMHp8bNPBj9RqGqMSnnJxny5WO3vHxYAodKx7h6w-PtuON84lICnhiJ06RzsWjZfdeaQYg4gCZmd2J6Hdq0_K32n3l3kFLg --kubeconfig=/root/def-ns-admin.conf 
User "def-ns-admin" set.

（3）配置上下文和当前上下文

[root@k8s-master ~]# kubectl config set-context def-ns-admin@kubernetes --cluster=kubernetes --user=def-ns-admin --kubeconfig=/root/def-ns-admin.conf 
Context "def-ns-admin@kubernetes" created.

[root@k8s-master ~]# kubectl config use-context def-ns-admin@kubernetes --kubeconfig=/root/def-ns-admin.conf 
Switched to context "def-ns-admin@kubernetes".

[root@k8s-master ~]# kubectl config view --kubeconfig=/root/def-ns-admin.conf 
apiVersion: v1
clusters:
- cluster:
    certificate-authority-data: REDACTED
    server: https://192.168.56.11:6443
  name: kubernetes
contexts:
- context:
    cluster: kubernetes
    user: def-ns-admin
  name: def-ns-admin@kubernetes
current-context: def-ns-admin@kubernetes
kind: Config
preferences: {}
users:
- name: def-ns-admin
  user:
    token: eyJhbGciOiJSUzI1NiIsImtpZCI6IiJ9.eyJpc3MiOiJrdWJlcm5ldGVzL3NlcnZpY2VhY2NvdW50Iiwia3ViZXJuZXRlcy5pby9zZXJ2aWNlYWNjb3VudC9uYW1lc3BhY2UiOiJkZWZhdWx0Iiwia3ViZXJuZXRlcy5pby9zZXJ2aWNlYWNjb3VudC9zZWNyZXQubmFtZSI6ImRlZi1ucy1hZG1pbi10b2tlbi1rOWZ6OSIsImt1YmVybmV0ZXMuaW8vc2VydmljZWFjY291bnQvc2VydmljZS1hY2NvdW50Lm5hbWUiOiJkZWYtbnMtYWRtaW4iLCJrdWJlcm5ldGVzLmlvL3NlcnZpY2VhY2NvdW50L3NlcnZpY2UtYWNjb3VudC51aWQiOiI1NmVkOTAxYy1kMDQyLTExZTgtODAxYS0wMDBjMjk3MmRjMWYiLCJzdWIiOiJzeXN0ZW06c2VydmljZWFjY291bnQ6ZGVmYXVsdDpkZWYtbnMtYWRtaW4ifQ.QfB5RR19nBv4-kFYyzW5-2n5Ksg-kON8lU18-COLBNfObQTDHs926m4k9f_5bto4YGncYi7sV_3oEec8ouW1FRjJWfY677L1IqIlwcuqc-g0DUo21zkjY_s3Lv3JSb_AfXUbZ7VTeWOhvwonqfK8uriGO1-XET-RBk1CE4Go1sL7X5qDgPjNO1g85D9IbIZG64VygplT6yZNc-b7tLNn_O49STthy6J0jdNk8lYxjy6UJohoTicy2XkZMHp8bNPBj9RqGqMSnnJxny5WO3vHxYAodKx7h6w-PtuON84lICnhiJ06RzsWjZfdeaQYg4gCZmd2J6Hdq0_K32n3l3kFLg

将/root/def-ns-admin.conf文件发送到宿主机，浏览器访问时选择Kubeconfig认证，载入该配置文件，点击登陆，即可实现访问，如图： 

二、总结

1、部署dashboard：

kubectl apply -f https://raw.githubusercontent.com/kubernetes/dashboard/master/src/deploy/recommended/kubernetes-dashboard.yaml

2、将Service改为Node Port方式进行访问：

kubectl patch svc kubernetes-dashboard -p '{"spec":{"type":"NodePort"}}' -n kube-system

3、访问认证：

认证时的账号必须为ServiceAccount：其作用是被dashboard pod拿来由kubenetes进行认证；认证方式有2种：
token：

• （1）创建ServiceAccount，根据其管理目标，使用rolebinding或clusterbinding绑定至合理的role或clusterrole；
• （2）获取此ServiceAccount的secret，查看secret的详细信息，其中就有token；
• （3）复制token到认证页面即可登录。

kubeconfig：把ServiceAccount的token封装为kubeconfig文件

• （1）创建ServiceAccount，根据其管理目标，使用rolebinding或clusterbinding绑定至合理的role或clusterrole；
• （2）kubectl get secret |awk '/^ServiceAccount/{print $1}'
• KUBE_TOKEN=$(kubectl get secret SERVICEACCOUNT_SECRET_NAME -o jsonpath={.data.token} | base64 -d)
• （3）生成kubeconfig文件

kubectl config set-cluster
kubectl config set-credentials NAME --token=$KUBE_TOKEN
kubectl config set-context
kubectl config use-context