K8s--07 configMap资源

目录

• 一、configMap资源
• 二、安全认证和RBACAPI
• 三、dashboard创建

一、configMap资源

configMap资源
 
1.为什么要用configMap？
将配置文件和POD解耦

2.congiMap里的配置文件是如何存储的？
键值对
key:value
文件名:配置文件的内容

3.configMap支持的配置类型
  直接定义的键值对 
  基于文件创建的键值对

4.configMap创建方式
  命令行
  资源配置清单 

5.configMap的配置文件如何传递到POD里
  变量传递
  数据卷挂载

6.命令行创建configMap
kubectl create configmap --help

kubectl create configmap nginx-config --from-literal=nginx_port=80 --from-literal=server_name=nginx.cookzhang.com

kubectl get cm
kubectl describe cm nginx-config 


7.POD环境变量形式引用configMap
kubectl explain pod.spec.containers.env.valueFrom.configMapKeyRef

cat >nginx-cm.yaml <<EOF
apiVersion: v1
kind: Pod
metadata: 
  name: nginx-cm
spec:
  containers:
  - name: nginx-pod
    image: nginx:1.14.0
    ports:
    - name: http 
      containerPort: 80
    env:
    - name: NGINX_PORT
      valueFrom:
        configMapKeyRef:
          name: nginx-config
          key: nginx_port
    - name: SERVER_NAME
      valueFrom:
        configMapKeyRef:
          name: nginx-config
          key: server_name 
EOF
kubectl create -f nginx-cm.yaml

8.查看pod是否引入了变量
[root@node1 ~/confimap]# kubectl exec -it nginx-cm /bin/bash
root@nginx-cm:~# echo ${NGINX_PORT}
80
root@nginx-cm:~# echo ${SERVER_NAME}
nginx.cookzhang.com
root@nginx-cm:~# printenv |egrep "NGINX_PORT|SERVER_NAME"
NGINX_PORT=80
SERVER_NAME=nginx.cookzhang.com

注意：
变量传递的形式，修改confMap的配置，POD内并不会生效
因为变量只有在创建POD的时候才会引用生效，POD一旦创建好，环境变量就不变了


8.文件形式创建configMap
创建配置文件：
cat >www.conf <<EOF
server {
        listen       80;
        server_name  www.cookzy.com;
        location / {
            root   /usr/share/nginx/html/www;
            index  index.html index.htm;
        }
    }
EOF

创建configMap资源：
kubectl create configmap nginx-www --from-file=www.conf=./www.conf 

查看cm资源
kubectl get cm
kubectl describe cm nginx-www

编写pod并以存储卷挂载模式引用configMap的配置
cat >nginx-cm-volume.yaml <<EOF
apiVersion: v1
kind: Pod
metadata: 
  name: nginx-cm
spec:
  containers:
  - name: nginx-pod
    image: nginx:1.14.0
    ports:
    - name: http 
      containerPort: 80

    volumeMounts:
    - name: nginx-www
      mountPath: /etc/nginx/conf.d/

  volumes:
  - name: nginx-www
    configMap:
     name: nginx-www
     items: 
     - key: www.conf
       path: www.conf
EOF

测试：
1.进到容器内查看文件
kubectl exec -it nginx-cm /bin/bash
cat /etc/nginx/conf.d/www.conf 
2.动态修改configMap
kubectl edit cm nginx-www

3.再次进入容器内观察配置会不会自动更新
cat /etc/nginx/conf.d/www.conf 
nginx -T


9.配置文件内容直接以数据格式直接存储在configMap里
创建config配置清单：
cat >nginx-configMap.yaml <<EOF
apiVersion: v1
kind: ConfigMap
metadata:
  name: nginx-config
  namespace: default
data:
  www.conf: |
    server {
            listen       80;
            server_name  www.cookzy.com;
            location / {
                root   /usr/share/nginx/html/www;
                index  index.html index.htm;
            }
        }
  blog.conf: |
    server {
            listen       80;
            server_name  blog.cookzy.com;
            location / {
                root   /usr/share/nginx/html/blog;
                index  index.html index.htm;
            }
        }


应用并查看清单:
kubectl create -f nginx-configMap.yaml
kubectl get cm
kubectl describe cm nginx-config 

创建POD资源清单并引用configMap
cat >nginx-cm-volume-all.yaml <<EOF
apiVersion: v1
kind: Pod
metadata: 
  name: nginx-cm
spec:
  containers:
  - name: nginx-pod
    image: nginx:1.14.0
    ports:
    - name: http 
      containerPort: 80
    volumeMounts:
    - name: nginx-config
      mountPath: /etc/nginx/conf.d/

  volumes:
  - name: nginx-config
    configMap:
     name: nginx-config
     items: 
     - key: www.conf
       path: www.conf
     - key: blog.conf
       path: blog.conf
EOF

应用并查看:
kubectl create -f nginx-cm-volume-all.yaml
kubectl get pod
kubectl describe pod nginx-cm 

进入容器内并查看：
kubectl exec -it nginx-cm /bin/bash
ls /etc/nginx/conf.d/
cat /etc/nginx/conf.d/www.conf

测试动态修改configMap会不会生效
kubectl edit cm nginx-config 

kubectl exec -it nginx-cm /bin/bash
ls /etc/nginx/conf.d/
cat /etc/nginx/conf.d/www.conf

二、安全认证和RBACAPI

Server是访问控制的唯一入口

在k8s平台上的操作对象都要经历三种安全相关的操作
1.认证操作
  http协议 token 认证令牌 
  ssl认证  kubectl需要证书双向认证
2.授权检查
  RBAC  基于角色的访问控制 
3.准入控制
  进一步补充授权机制，一般在创建，删除，代理操作时作补充

k8s的api账户分为2类
  1.实实在在的用户 人类用户 userAccount
  2.POD客户端 serviceAccount 默认每个POD都有认真信息

RBAC就要角色的访问控制
  你这个账号可以拥有什么权限
  
以traefik举例：
1.创建了账号 ServiceAccount:traefik-ingress-controller
2.创建角色   ClusterRole:   traefik-ingress-controller
  Role  POD相关的权限
  ClusterRole namespace级别操作 
3.将账户和权限角色进行绑定     traefik-ingress-controller
  RoleBinding
  ClusterRoleBinding
4.创建POD时引用ServiceAccount
  serviceAccountName: traefik-ingress-controller


注意！！！
kubeadm安装的k8s集群，证书默认只有1年

三、dashboard创建

k8s 

1.官方项目地址
https://github.com/kubernetes/dashboard

2.下载配置文件
wget https://raw.githubusercontent.com/kubernetes/dashboard/v2.0.0-rc5/aio/deploy/recommended.yaml

3.修改配置文件
 39 spec:
 40   type: NodePort
 41   ports:
 42     - port: 443
 43       targetPort: 8443
 44       nodePort: 30000

4.应用资源配置
kubectl create -f recommended.yaml

5.创建管理员账户并应用
https://github.com/kubernetes/dashboard/blob/master/docs/user/access-control/creating-sample-user.md

cat > dashboard-admin.yaml<<EOF
apiVersion: v1
kind: ServiceAccount
metadata:
  name: admin-user
  namespace: kubernetes-dashboard
---
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
EOF
kubectl create -f dashboard-admin.yaml

6.查看资源并获取token
kubectl get pod -n kubernetes-dashboard -o wide
kubectl get svc -n kubernetes-dashboard
kubectl get secret  -n kubernetes-dashboard
kubectl -n kubernetes-dashboard describe secret $(kubectl -n kubernetes-dashboard get secret | grep admin-user | awk '{print $1}')

7.浏览器访问
https://10.0.0.11:30000
google浏览器打不开就换火狐浏览器
黑科技 


x.报错总结
{"level":"error","msg":"Error scraping node metrics: the server could not find the requested resource (get nodes.metrics.k8s.io)","time":"2020-03-03T09:57:00Z"}

Skipping metric because of error: Metric label not set

原因：
没有安装metrics监控组建