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类型的数据是一个map类型,要求value是base64编码格式:
$ echo -n "admin" | base64
YWRtaW4=
$ echo -n "1f2d1e2e67df" | base64
MWYyZDFlMmU2N2Rm
secrets.yml
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
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
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
可以直接用kubectl
命令来创建用于docker registry认证的secret:
$ 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:
$ 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
:
apiVersion: v1
kind: Pod
metadata:
name: foo
spec:
containers:
- name: foo
image: janedoe/awesomeapp:v1
imagePullSecrets:
- name: myregistrykey
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。
$ 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