Secret · kubernetes完整攻略

# Secret Secret解决了密码、token、密钥等敏感数据的配置问题，而不需要把这些敏感数据暴露到镜像或者Pod Spec中。Secret可以以Volume或者环境变量的方式使用。 Secret有三种类型： * **Service Account** ：用来访问Kubernetes API，由Kubernetes自动创建，并且会自动挂载到Pod的`/run/secrets/kubernetes.io/serviceaccount`目录中； * **Opaque** ：base64编码格式的Secret，用来存储密码、密钥等； * **kubernetes.io/dockerconfigjson** ：用来存储私有docker registry的认证信息。 ## Opaque Secret Opaque类型的数据是一个map类型，要求value是base64编码格式： ```sh $ echo -n "admin" | base64 YWRtaW4= $ echo -n "1f2d1e2e67df" | base64 MWYyZDFlMmU2N2Rm ``` secrets.yml ```yaml apiVersion: v1 kind: Secret metadata: name: mysecret type: Opaque data: password: MWYyZDFlMmU2N2Rm username: YWRtaW4= ``` 接着，就可以创建secret了：`kubectl create -f secrets.yml`。创建好secret之后，有两种方式来使用它： * 以Volume方式 * 以环境变量方式 ### 将Secret挂载到Volume中 ```yaml apiVersion: v1 kind: Pod metadata: labels: name: db name: db spec: volumes: - name: secrets secret: secretName: mysecret containers: - image: gcr.io/my_project_id/pg:v1 name: db volumeMounts: - name: secrets mountPath: "/etc/secrets" readOnly: true ports: - name: cp containerPort: 5432 hostPort: 5432 ``` ### 将Secret导出到环境变量中 ```yaml apiVersion: extensions/v1beta1 kind: Deployment metadata: name: wordpress-deployment spec: replicas: 2 strategy: type: RollingUpdate template: metadata: labels: app: wordpress visualize: "true" spec: containers: - name: "wordpress" image: "wordpress" ports: - containerPort: 80 env: - name: WORDPRESS_DB_USER valueFrom: secretKeyRef: name: mysecret key: username - name: WORDPRESS_DB_PASSWORD valueFrom: secretKeyRef: name: mysecret key: password ``` ## kubernetes.io/dockerconfigjson 可以直接用`kubectl`命令来创建用于docker registry认证的secret： ```sh $ kubectl create secret docker-registry myregistrykey --docker-server=DOCKER_REGISTRY_SERVER --docker-username=DOCKER_USER --docker-password=DOCKER_PASSWORD --docker-email=DOCKER_EMAIL secret "myregistrykey" created. ``` 也可以直接读取`~/.docker/config.json`的内容来创建： ```sh $ cat ~/.docker/config.json | base64 $ cat > myregistrykey.yaml <<EOF apiVersion: v1 kind: Secret metadata: name: myregistrykey data: .dockerconfigjson: UmVhbGx5IHJlYWxseSByZWVlZWVlZWVlZWFhYWFhYWFhYWFhYWFhYWFhYWFhYWFhYWFhYWxsbGxsbGxsbGxsbGxsbGxsbGxsbGxsbGxsbGxsbGx5eXl5eXl5eXl5eXl5eXl5eXl5eSBsbGxsbGxsbGxsbGxsbG9vb29vb29vb29vb29vb29vb29vb29vb29vb25ubm5ubm5ubm5ubm5ubm5ubm5ubm5ubmdnZ2dnZ2dnZ2dnZ2dnZ2dnZ2cgYXV0aCBrZXlzCg== type: kubernetes.io/dockerconfigjson EOF $ kubectl create -f myregistrykey.yaml ``` 在创建Pod的时候，通过`imagePullSecrets`来引用刚创建的`myregistrykey`: ```yaml apiVersion: v1 kind: Pod metadata: name: foo spec: containers: - name: foo image: janedoe/awesomeapp:v1 imagePullSecrets: - name: myregistrykey ``` ### Service Account Service Account用来访问Kubernetes API，由Kubernetes自动创建，并且会自动挂载到Pod的`/run/secrets/kubernetes.io/serviceaccount`目录中。 ```sh $ kubectl run nginx --image nginx deployment "nginx" created $ kubectl get pods NAME READY STATUS RESTARTS AGE nginx-3137573019-md1u2 1/1 Running 0 13s $ kubectl exec nginx-3137573019-md1u2 ls /run/secrets/kubernetes.io/serviceaccount ca.crt namespace token ```