Kubernetes Dashboard搭建流程

一. 背景

    通過 二進制方式 完成了kubernetes的安裝，可以正常使用kubernetes的各種功能了，但是有點不足的是，只能通過命令查看/創建/刪除/修改等操作，沒有直觀的Web UI界面感受直觀，因此搭建kubernetes dashboard來進一步的管理容器應用。

二. 操作

    1. 調研所需的dashboard配置版本
        因爲kubernetes已搭建完成，而且版本比較新v1.16.1,一般普通的dashboard會導致其與Kubernetes服務不兼容。
        官網調研，kubernetesv1.16.1所需的dashboard需要 v2.0以上，如果要展示各節點的cpu/內存/磁盤空間等使用情況，則需要安裝metrics
    2. 跨網下載兩個鏡像並導入到本地倉庫中
        因爲國內無法直接訪問相關的docker倉庫，則需要一臺網外服務器做跳板支持

網外]# docker pull kubernetesui/metrics-scraper:v1.0.1
網外]# docker pull docker.io/kubernetesui/dashboard:v2.0.0-beta4
網外]# docker save -i dashboard.tar docker.io/kubernetesui/dashboard:v2.0.0-beta4
網外]# docker save -i metrics.tar kubernetesui/metrics-scraper:v1.0.1
master]# docker load <  docker.io/kubernetesui/dashboard:v2.0.0-beta4
master]# docker load < kubernetesui/metrics-scraper:v1.0.1
master]# docker tag docker.io/kubernetesui/dashboard:v2.0.0-beta4 192.168.89.132:5000/kubernetesui/dashboard:v2.0.0-beta4
master]# docker tag kubernetesui/metrics-scraper:v1.0.1 192.168.89.132:5000/kubernetesui/metrics-scraper:v1.0.1
master]# docker push  192.168.89.132:5000/kubernetesui/dashboard:v2.0.0-beta4
master]# docker push  192.168.89.132:5000/kubernetesui/metrics-scraper:v1.0.1

    3. 到官網下載相應的dashboard yaml文件，並做修改
        位置：https://raw.githubusercontent.com/kubernetes/dashboard/v2.0.0-beta4/aio/deploy/recommended.yaml
        修改鏡像位置等信息 recommended.yaml

# Copyright 2017 The Kubernetes Authors.
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
#     http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.

apiVersion: v1
kind: Namespace
metadata:
  name: kubernetes-dashboard

---

apiVersion: v1
kind: ServiceAccount
metadata:
  labels:
    k8s-app: kubernetes-dashboard
  name: kubernetes-dashboard
  namespace: kubernetes-dashboard

---

kind: Service
apiVersion: v1
metadata:
  labels:
    k8s-app: kubernetes-dashboard
  name: kubernetes-dashboard
  namespace: kubernetes-dashboard
spec:
  ports:
    - port: 443
      targetPort: 8443
      nodePort: 30000
  selector:
    k8s-app: kubernetes-dashboard
  type: NodePort

---

apiVersion: v1
kind: Secret
metadata:
  labels:
    k8s-app: kubernetes-dashboard
  name: kubernetes-dashboard-certs
  namespace: kubernetes-dashboard
type: Opaque

---

apiVersion: v1
kind: Secret
metadata:
  labels:
    k8s-app: kubernetes-dashboard
  name: kubernetes-dashboard-csrf
  namespace: kubernetes-dashboard
type: Opaque
data:
  csrf: ""

---

apiVersion: v1
kind: Secret
metadata:
  labels:
    k8s-app: kubernetes-dashboard
  name: kubernetes-dashboard-key-holder
  namespace: kubernetes-dashboard
type: Opaque

---

kind: ConfigMap
apiVersion: v1
metadata:
  labels:
    k8s-app: kubernetes-dashboard
  name: kubernetes-dashboard-settings
  namespace: kubernetes-dashboard

---

kind: Role
apiVersion: rbac.authorization.k8s.io/v1
metadata:
  labels:
    k8s-app: kubernetes-dashboard
  name: kubernetes-dashboard
  namespace: kubernetes-dashboard
rules:
  # Allow Dashboard to get, update and delete Dashboard exclusive secrets.
  - apiGroups: [""]
    resources: ["secrets"]
    resourceNames: ["kubernetes-dashboard-key-holder", "kubernetes-dashboard-certs", "kubernetes-dashboard-csrf"]
    verbs: ["get", "update", "delete"]
    # Allow Dashboard to get and update 'kubernetes-dashboard-settings' config map.
  - apiGroups: [""]
    resources: ["configmaps"]
    resourceNames: ["kubernetes-dashboard-settings"]
    verbs: ["get", "update"]
    # Allow Dashboard to get metrics.
  - apiGroups: [""]
    resources: ["services"]
    resourceNames: ["heapster", "dashboard-metrics-scraper"]
    verbs: ["proxy"]
  - apiGroups: [""]
    resources: ["services/proxy"]
    resourceNames: ["heapster", "http:heapster:", "https:heapster:", "dashboard-metrics-scraper", "http:dashboard-metrics-scraper"]
    verbs: ["get"]

---

kind: ClusterRole
apiVersion: rbac.authorization.k8s.io/v1
metadata:
  labels:
    k8s-app: kubernetes-dashboard
  name: kubernetes-dashboard
rules:
  # Allow Metrics Scraper to get metrics from the Metrics server
  - apiGroups: ["metrics.k8s.io"]
    resources: ["pods", "nodes"]
    verbs: ["get", "list", "watch"]

---

apiVersion: rbac.authorization.k8s.io/v1
kind: RoleBinding
metadata:
  labels:
    k8s-app: kubernetes-dashboard
  name: kubernetes-dashboard
  namespace: kubernetes-dashboard
roleRef:
  apiGroup: rbac.authorization.k8s.io
  kind: Role
  name: kubernetes-dashboard
subjects:
  - kind: ServiceAccount
    name: kubernetes-dashboard
    namespace: kubernetes-dashboard

---

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

---

kind: Deployment
apiVersion: apps/v1
metadata:
  labels:
    k8s-app: kubernetes-dashboard
  name: kubernetes-dashboard
  namespace: kubernetes-dashboard
spec:
  replicas: 1
  revisionHistoryLimit: 10
  selector:
    matchLabels:
      k8s-app: kubernetes-dashboard
  template:
    metadata:
      labels:
        k8s-app: kubernetes-dashboard
    spec:
      containers:
        - name: kubernetes-dashboard
          image: 192.168.89.132:5000/kubernetesui/dashboard:v2.0.0-beta4
          imagePullPolicy: Always
          ports:
            - containerPort: 8443
              protocol: TCP
          args:
            - --auto-generate-certificates
            - --namespace=kubernetes-dashboard
            # Uncomment the following line to manually specify Kubernetes API server Host
            # If not specified, Dashboard will attempt to auto discover the API server and connect
            # to it. Uncomment only if the default does not work.
            # - --apiserver-host=http://my-address:port
          volumeMounts:
            - name: kubernetes-dashboard-certs
              mountPath: /certs
              # Create on-disk volume to store exec logs
            - mountPath: /tmp
              name: tmp-volume
          livenessProbe:
            httpGet:
              scheme: HTTPS
              path: /
              port: 8443
            initialDelaySeconds: 30
            timeoutSeconds: 30
      volumes:
        - name: kubernetes-dashboard-certs
          secret:
            secretName: kubernetes-dashboard-certs
        - name: tmp-volume
          emptyDir: {}
      serviceAccountName: kubernetes-dashboard
      # Comment the following tolerations if Dashboard must not be deployed on master
      tolerations:
        - key: node-role.kubernetes.io/master
          effect: NoSchedule

---

kind: Service
apiVersion: v1
metadata:
  labels:
    k8s-app: dashboard-metrics-scraper
  name: dashboard-metrics-scraper
  namespace: kubernetes-dashboard
spec:
  ports:
    - port: 8000
      targetPort: 8000
  selector:
    k8s-app: dashboard-metrics-scraper

---

kind: Deployment
apiVersion: apps/v1
metadata:
  labels:
    k8s-app: dashboard-metrics-scraper
  name: dashboard-metrics-scraper
  namespace: kubernetes-dashboard
spec:
  replicas: 1
  revisionHistoryLimit: 10
  selector:
    matchLabels:
      k8s-app: dashboard-metrics-scraper
  template:
    metadata:
      labels:
        k8s-app: dashboard-metrics-scraper
    spec:
      containers:
        - name: dashboard-metrics-scraper
          image: 192.168.89.132:5000/kubernetesui/metrics-scraper:v1.0.1
          ports:
            - containerPort: 8000
              protocol: TCP
          livenessProbe:
            httpGet:
              scheme: HTTP
              path: /
              port: 8000
            initialDelaySeconds: 30
            timeoutSeconds: 30
          volumeMounts:
          - mountPath: /tmp
            name: tmp-volume
      serviceAccountName: kubernetes-dashboard
      # Comment the following tolerations if Dashboard must not be deployed on master
      tolerations:
        - key: node-role.kubernetes.io/master
          effect: NoSchedule
      volumes:
        - name: tmp-volume
          emptyDir: {}			

    4. 執行kubectl命令
        

master]# kubectl create -f recommended.yaml

    5. 火狐瀏覽器訪問一臺node節點,一定是火狐瀏覽器，谷歌和ie瀏覽器無法認證
        

https://192.168.89.133:30000

    6. 找出token，並在頁面上輸入token登錄
        

master]# kubectl -n kubernetes-dashboard describe secret $(kubectl -n kubernetes-dashboard get secret | grep kubernetes-dashboard | awk '{print $1}')
Name:         kubernetes-dashboard-certs
Namespace:    kubernetes-dashboard
Labels:       k8s-app=kubernetes-dashboard
Annotations:  <none>

Type:  Opaque

Data
====


Name:         kubernetes-dashboard-csrf
Namespace:    kubernetes-dashboard
Labels:       k8s-app=kubernetes-dashboard
Annotations:  <none>

Type:  Opaque

Data
====
csrf:  256 bytes


Name:         kubernetes-dashboard-key-holder
Namespace:    kubernetes-dashboard
Labels:       <none>
Annotations:  <none>

Type:  Opaque

Data
====
pub:   459 bytes
priv:  1679 bytes


Name:         kubernetes-dashboard-token-wtqxq
Namespace:    kubernetes-dashboard
Labels:       <none>
Annotations:  kubernetes.io/service-account.name: kubernetes-dashboard
              kubernetes.io/service-account.uid: 542b2b68-cd41-40fe-811e-f7a5d52e6393

Type:  kubernetes.io/service-account-token

Data
====
ca.crt:     1090 bytes
namespace:  20 bytes
token:      eyJhbGciOiJSUzI1NiIsImtpZCI6ImsxbF9vUHFTbWxSbk1ZTWN5QmFuUEFhcDhpRXlQWFllR2RObE5EMjdTYWcifQ.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.FF2H_r0M8UOZnhhsluDQ3797pF8_VkPWKEVN4n8at9GrE63VpOhioTx4q-JBLC3mJliJCABybr7GFQiNvu6Q8wUPvlYfhmIdtQqhuyKMfBD9s_C7Mz_pQBnqTulxGUGE-dXFqQcAgpWZgXS9Zgaxcl3B4lDyzV50XfU5-mGpF8dMkTrJTktvVosEQgLJxhWFzeuUg5MPo27s7Y8Idh60RpASMbvBbWH2b1-CUHCPDqyxL_Wqgia0R7wn8Pu9gvNDKfekrutn7n4qnBTngvQFcBX7VWLcEIBvRUW4IJ8ouIcMljv_MwGSHwplLa0_Jcwumr0xeqo4zH7LJbH5y9wffw

            最後有token值，複製到頁面登錄頁即可

 

三. 後續

問題1：第二天登錄dashboard發現無法登錄了，查看pods運行情況，發現dashboard 鏡像無法下載，開始排查

1. 先刪除重新創建 recommended.yaml

master]# kubectl delete -f recommended.yaml
master]# kubectl create -f recommended.yaml

結果仍然是一樣的，dashboard無法運行

2. 查看以下私有倉庫是否正常

master]# ss -anptu | grep :5000
沒有相應的進程，原來是私有倉庫問題，現重啓私有倉庫並開機自啓。
master]# systemctl restart docker-distribution
master]# systemctl enable docker-distribution
master]# systemctl status docker-distribution
Active: active (running) since Thu 2020-05-07 09:43:56 CST; 29s ago
master]# ss -anptu | grep 5000
tcp    LISTEN     0      128    [::]:5000               [::]:*                   users:(("registry",pid=8805,fd=3))

3. 再次打開火狐瀏覽器，通過token登錄，發現輸入token後點擊登錄沒有反應，懷疑是token失效了，重新獲取token值

使用新的token值登錄成功了，由此可知，一段時間之後，token值失效，需要重新獲取新的token值。