09-kubernetes configMap secret

目录

• 配置容器化应用配置的方式
  • 命令创建和测试configMap
    • 创建一个Pod 挂在测试
  • 命令行文件类创建方式
    • 创建Pod测试
    • 创建后测试
  • 贴近实际进行测试
    • 创建后测试
• secret
  • 举例测试 generic

配置容器化应用配置的方式

1. 自定义命令行参数来实现;
   1. command
   2. args []
2. 把配置文件直接打入进项;
3. 环境变量实现, 容器从物理机中的环境变量来导入配置
   1. 所配置的应用支持从环境变量中来读取
   2. 用预处理脚本entrypoint处理,通过环境变量传递过来的配置
4. 存储卷;通过挂在对应的已经存放了配置文件的存储卷上

configMap

将配置文件从镜像中解耦, 从而增强了应用的可以执行以及应用的复制性.

命令创建和测试configMap

命令行键值对创建

kubectl describe configmap nginx-www -o yaml
[root@master volume]# kubectl create configmap nginx-config --from-literal=nginx_port=80 --from-literal=server_name=myapp.sijiayong.com
configmap/nginx-config created
[root@master volume]# kubectl get configmap
NAME           DATA   AGE
nginx-config   2      7s
[root@master volume]# kubectl describe configmap nginx-config
Name:         nginx-config
Namespace:    default
Labels:       <none>
Annotations:  <none>

Data
====
nginx_port:
----
80
server_name:
----
myapp.sijiayong.com
Events:  <none>

创建一个Pod 挂在测试

配置清单如下:

[root@master configmap]# cat pod-configmap.yaml 
apiVersion: v1
kind: Pod
metadata:
  name: pod-cm
  namespace: default
  labels:
    app: myapp
    tier: frontend
  annotations:
    jubaozhu.com/created-by: "cluster admin"
spec:
  containers:
  - name: myapp
    image: ikubernetes/myapp:v1
    ports:
    - name: http
      containerPort: 80
    env:                            # 这里使用env, 表示容器中会用环境变量导入
    - name: NGINX_SERVER_PORT       # 这里的name表示容器中的key值
      valueFrom:
        configMapKeyRef:
          name: nginx-config        # 这里name是指向configMap对应的名称
          key: nginx_port           # 表示容器中key 所对应的 value的值, 此处取值的地方是定义的configMap中的对应的value值
    - name: NGINX_SERVER_NAME       # 因为要导入两个值,所以要写两份, 写法和上面的导入环境变量的方式相同
      valueFrom:
        configMapKeyRef:
          name: nginx-config
          key: server_name

创建后测试

[root@master configmap]# kubectl apply -f pod-configmap.yaml 
pod/pod-cm created
[root@master configmap]# kubectl get pod -o wide
NAME          READY   STATUS    RESTARTS   AGE   IP            NODE                NOMINATED NODE   READINESS GATES
pod-cm        1/1     Running   0          8s    10.244.1.30   node03.kubernetes   <none>           <none>

创建Pod后,进入到对应的容器中查看环境变量

把端口变更为8080

[root@master configmap]# kubectl exec -it pod-cm -- /bin/sh
/ # env
MYAPP_SVC_PORT_80_TCP_ADDR=10.98.57.156
KUBERNETES_PORT=tcp://10.96.0.1:443
KUBERNETES_SERVICE_PORT=443
MYAPP_SVC_PORT_80_TCP_PORT=80
HOSTNAME=pod-cm
SHLVL=1
MYAPP_SVC_PORT_80_TCP_PROTO=tcp
HOME=/root
NGINX_SERVER_PORT=80
NGINX_SERVER_NAME=myapp.sijiayong.com
... ...
... ...

可以通过命令行edit编辑configMap

[root@master configmap]# kubectl edit configmap nginx-config
configmap/nginx-config edited
[root@master configmap]# kubectl describe configmap nginx-config
Name:         nginx-config
Namespace:    default
Labels:       <none>
Annotations:  <none>

Data
====
nginx_port:
----
8080
server_name:
----
myapp.sijiayong.com
Events:  <none>

修改之后, 需要些许时间等待后,容器中的环境变量就会变更,需要再次进入容器后查看环境变量中的端口的值是否有变化

命令行文件类创建方式

首先需要手动编辑一个相应的配置文件

[root@master configmap]# cat www.conf 
server {
    server_name myapp.sijiayong.com;
    listen 80;
    root /data/web/html/;
}

然后使用命令创建如下:

[root@master configmap]# kubectl create configmap nginx-www --from-file=www.conf        # 这里只有一个等号, 表示 key 就是文件名称, 而value 是文件内容
configmap/nginx-www created
[root@master configmap]# kubectl get configmap
NAME           DATA   AGE
nginx-config   2      2m41s
nginx-www      1      4s
[root@master configmap]# kubectl describe configmap nginx-www
Name:         nginx-www
Namespace:    default
Labels:       <none>
Annotations:  <none>

Data
====
www.conf:
----
server {
    server_name myapp.sijiayong.com;
    listen 80;
    root /data/web/html/;
}

Events:  <none>
[root@master configmap]# kubectl get configmap nginx-www -o yaml
apiVersion: v1
data:
  www.conf: |
    server {
        server_name myapp.sijiayong.com;
        listen 80;
        root /data/web/html/;
    }
kind: ConfigMap
metadata:
  creationTimestamp: "2019-08-06T08:44:37Z"
  name: nginx-www
  namespace: default
  resourceVersion: "3850257"
  selfLink: /api/v1/namespaces/default/configmaps/nginx-www
  uid: 81050135-532c-4f0e-8fcf-99727cc2c498

创建Pod测试

创建相应清单文件

[root@master configmap]# cat pod-configmap-2.yaml 
apiVersion: v1
kind: Pod
metadata:
  name: pod-cm-2
  namespace: default
  labels:
    app: myapp
    tier: frontend
  annotations:
    jubaozhu.com/created-by: "cluster admin"
spec:
  containers:
  - name: myapp
    image: ikubernetes/myapp:v1
    ports:
    - name: http
      containerPort: 80
    volumeMounts:                       # 可直接挂在configMap到Pod中
    - name: nginxconf                   # 这里指定卷名称
      mountPath: /etc/nginx/config.d/   # 这里指定挂在的路径
      readOnly: true                    # 这里表示当挂载失败的时候,容器能否启动成功,True表示可以正常启动,否则一点挂载失败,Pod的状态是Error
  volumes:                      # 定义一个卷, 实质上是一个configMap
  - name: nginxconf             # 卷名称
    configMap:
      name: nginx-config        # 这里指定 configMap对应的名称

创建后测试

[root@master configmap]# kubectl apply -f pod-configmap-2.yaml 
pod/pod-cm-2 created
[root@master configmap]# kubectl get pods -o wide
NAME          READY   STATUS    RESTARTS   AGE   IP            NODE                NOMINATED NODE   READINESS GATES
pod-cm-2      1/1     Running   0          5s    10.244.2.29   node02.kubernetes   <none>           <none>

然后进入Pod中查看挂在是否正常

[root@master configmap]# kubectl exec -it pod-cm-2 -- /bin/sh
/ # cd /etc/nginx/config.d/
/etc/nginx/config.d # ls -l
total 0
lrwxrwxrwx    1 root     root            17 Aug  6 09:12 nginx_port -> ..data/nginx_port
lrwxrwxrwx    1 root     root            18 Aug  6 09:12 server_name -> ..data/server_name
/etc/nginx/config.d # cat server_name 
myapp.sijiayong.com/etc/nginx/config.d # cat nginx_port         # servername显示正常
8080/etc/nginx/config.d # exit                                  # 端口显示正常

同样也支持在线修改, 需要些许时间后就容器中的对应的值就会产生变化

贴近实际进行测试

上面创建了一个nginx-www 的一个正常的nginx主机的一个配置文件, 下面挂在到Pod中尝试访问是否正常

[root@master configmap]# vim pod-configmap-3.yaml
apiVersion: v1
kind: Pod
metadata:
  name: pod-cm-3
  namespace: default
  labels:
    app: myapp
    tier: frontend
  annotations:
    jubaozhu.com/created-by: "cluster admin"
spec:
  containers:
  - name: myapp
    image: ikubernetes/myapp:v1
    ports:
    - name: http
      containerPort: 80
    volumeMounts:
    - name: nginxconf
      mountPath: /etc/nginx/conf.d/     # 挂载点为实际的nginx配置文件目录
      readOnly: true
  volumes:
  - name: nginxconf
    configMap:
      name: nginx-www

创建后测试

[root@master configmap]# kubectl apply -f pod-configmap-3.yaml 
pod/pod-cm-3 created
[root@master configmap]# kubectl get pods -o wide
NAME          READY   STATUS    RESTARTS   AGE   IP            NODE                NOMINATED NODE   READINESS GATES
pod-cm-3      1/1     Running   0          6s    10.244.3.33   node01.kubernetes   <none>           <none>

进入Pod中查看

[root@master configmap]# kubectl exec -it pod-cm-3 -- /bin/sh
/ # cd /etc/nginx/conf.d/
/etc/nginx/conf.d # ls
www.conf
/etc/nginx/conf.d # cat www.conf 
server {
    server_name myapp.sijiayong.com;
    listen 8088;
    root /data/web/html/;
}

因为配置的nginx虚拟主机对应的目录不存在,下面来手动创建目录和写入测试内容

[root@master configmap]# kubectl exec -it pod-cm-3 -- /bin/sh
/ # mkdir /data/web/html -p
/ # echo '<h1>Nginx Server configured by ConfigMap</h1>' > /data/web/html/index.html

集群外部测试访问:

<h1>Nginx Server configured by ConfigMap</h1>
[root@master configmap]# curl 10.244.3.33:80

需要注意的是, 如果在线修改了configMap后, 这里需要手动进入到Pod中, 重载一下nginx才可以, 否则不生效

secret

secret 不实用明文进行展示, 而是使用 base64 编码

三种类型:

1. generic 通用的secret, 一般保存密码使用
2. tls 保存证书和对应的秘钥
3. docker-registry docker的认证信息

举例测试 generic

通过命令的形式创建一个 secret

[root@master configmap]# kubectl create secret generic mysql-root-password --from-literal=passwork=MyP@ss123
secret/mysql-root-password created
[root@master configmap]# kubectl get secret
NAME                    TYPE                                  DATA   AGE
default-token-bc86p     kubernetes.io/service-account-token   3      28d
mysql-root-password     Opaque                                1      4s         # 这里看到创建成功
tomcat-ingress-secret   kubernetes.io/tls                     2      5d21h
[root@master configmap]# kubectl describe secret mysql-root-password
Name:         mysql-root-password
Namespace:    default
Labels:       <none>
Annotations:  <none>

Type:  Opaque

Data
====
passwork:  9 bytes          # value的值 没有被直接显示出来

解密

[root@master configmap]# kubectl get secret mysql-root-password -o yaml
apiVersion: v1
data:
  passwork: TXlQQHNzMTIz                # base64 编码格式的密码加密方式
kind: Secret
metadata:
  creationTimestamp: "2019-08-07T01:07:11Z"
  name: mysql-root-password
  namespace: default
  resourceVersion: "3942726"
  selfLink: /api/v1/namespaces/default/secrets/mysql-root-password
  uid: f73164b5-8619-42c4-8186-c13ae8ebd89d
type: Opaque
[root@master configmap]# echo TXlQQHNzMTIz | base64 -d              # 解密........
MyP@ss123[root@master configmap]#

创建Pod 应用此 secret

[root@master configmap]# cat pod-secret-1.yaml 
apiVersion: v1
kind: Pod
metadata:
  name: pod-secret-1
  namespace: default
  labels:
    app: myapp
    tier: frontend
  annotations:
    jubaozhu.com/created-by: "cluster admin"
spec:
  containers:
  - name: myapp
    image: ikubernetes/myapp:v1
    ports:
    - name: http
      containerPort: 80
    env:
    - name: MYSQL_ROOT_PASSWORD
      valueFrom:
        secretKeyRef:
          name: mysql-root-password
          key: passwork

创建查看

[root@master configmap]# kubectl apply -f pod-secret-1.yaml 
pod/pod-secret-1 created
[root@master configmap]# kubectl get pods
NAME           READY   STATUS    RESTARTS   AGE
pod-secret-1   1/1     Running   0          2s
[root@master configmap]# kubectl exec -it pod-secret-1 -- /bin/sh
/ # env
MYAPP_SVC_PORT_80_TCP_ADDR=10.98.57.156
KUBERNETES_SERVICE_PORT=443
KUBERNETES_PORT=tcp://10.96.0.1:443
MYAPP_SVC_PORT_80_TCP_PORT=80
HOSTNAME=pod-secret-1
SHLVL=1
MYAPP_SVC_PORT_80_TCP_PROTO=tcp
HOME=/root
MYSQL_ROOT_PASSWORD=MyP@ss123
... ...
... ...