k8s学习-CKS真题-ImagePolicyWebhook容器镜像扫描

Context
cluster上设置了容器镜像扫描器，但尚未完全集成到 cluster 的配置中。
完成后，容器镜像扫描器应扫描并拒绝易受攻击的镜像的使用。
Task
注意：你必须在 cluster 的 master 节点上完成整个考题，所有服务和文件都已被准备好并放置在该节点上。
给定一个目录 /etc/kubernetes/epconfig 中不完整的配置，
以及具有 HTTPS 端点 https://image-bouncer-webhook.default.svc:1323/image_policy 的功能性容器镜像扫描器：
1. 启用必要的插件来创建镜像策略
2. 校验控制配置并将其更改为隐式拒绝（implicit deny）
3. 编辑配置以正确指向提供的 HTTPS 端点
最后，通过尝试部署易受攻击的资源 /cks/img/web1.yaml 来测试配置是否有效。

mkdir -p /etc/kubernetes/epconfig
vim /etc/kubernetes/epconfig/admission_configuration.json

{
  "imagePolicy": {
     "kubeConfigFile": "/etc/kubernetes/kube-image-bouncer.yml",
     "allowTTL": 50,
     "denyTTL": 50,
     "retryBackoff": 500,
     "defaultAllow": true
  }
}

vim /etc/kubernetes/epconfig/kubeconfig.yaml

apiVersion: v1
kind: Config
# clusters refers to the remote service.
clusters:
- cluster:
    certificate-authority: /etc/kubernetes/epconfig/external-cert.pem  # CA for verifying the remote service.
    server: server  # URL of remote service to query. Must use 'https'.
  name: image-checker
contexts:
- context:
    cluster: image-checker
    user: api-server
  name: image-checker
current-context: image-checker
preferences: {}
# users refers to the API server's webhook configuration.
users:
- name: api-server
  user:
    client-certificate: /etc/kubernetes/epconfig/apiserver-client-cert.pem     # cert for the webhook admission controller to use
    client-key:  /etc/kubernetes/epconfig/apiserver-client-key.pem             # key matching the cert

mkdir -p /cks/img/
vim /cks/img/web1.yaml

apiVersion: v1
kind: ReplicationController
metadata:
  name: nginx-latest
spec:
  replicas: 1
  selector:
    app: nginx-latest
  template:
    metadata:
      name: nginx-latest
      labels:
        app: nginx-latest
    spec:
      containers:
      - name: nginx-latest
        image: nginx
        ports:
        - containerPort: 80

vim /etc/kubernetes/epconfig/adminssion_configuration.json

defaultAllow: false

vim /etc/kubernetes/epconfig/kubeconfig.yaml

server: https://image-bouncer-webhook.default.svc:1323/image_policy

vim /etc/kubernetes/manifests/kube-apiserver.yaml

--enable-admission-plugins=NodeRestriction,ImagePolicyWebhook
--admission-control-config-file=/etc/kubernetes/epconfig/adminssion_configuration.json

systemctl daemon-reload
systemctl restart kubelet

kubectl create -f /cks/img/web1.yaml
kubectl describe rc nginx-latest