跳转至

生成 K8s 审计日志

默认 Kubernetes 集群不会生成审计日志信息。通过以下配置，可以开启 Kubernetes 的审计日志功能。

Note

公有云环境中可能无法控制 kubernetes 审计日志输出及输出路径。

  1. 准备审计日志的 Policy 文件
  2. 配置 API 服务器，开启审计日志
  3. 重启并验证

准备审计日志 Policy 文件

点击查看审计日志 Policy YAML 文件
policy.yaml
apiVersion: audit.k8s.io/v1
kind: Policy
# Don't generate audit events for all requests in RequestReceived stage.
omitStages:
  - "ResponseStarted"
  - "RequestReceived"
  - "Panic"
rules:
  # The following requests were manually identified as high-volume and low-risk,
  # so drop them.
  - level: None
    users: ["system:kube-proxy"]
    verbs: ["watch"]
    resources:
      - group: "" # core
        resources: ["endpoints", "services", "services/status"]
  - level: None
    # Ingress controller reads `configmaps/ingress-uid` through the unsecured port.
    # TODO(#46983): Change this to the ingress controller service account.
    users: ["system:unsecured"]
    namespaces: ["kube-system"]
    verbs: ["get"]
    resources:
      - group: "" # core
        resources: ["configmaps"]
  - level: None
    users: ["kubelet"] # legacy kubelet identity
    verbs: ["get"]
    resources:
      - group: "" # core
        resources: ["nodes", "nodes/status"]
  - level: None
    userGroups: ["system:nodes"]
    verbs: ["get"]
    resources:
      - group: "" # core
        resources: ["nodes", "nodes/status"]
  - level: None
    users:
      - system:kube-controller-manager
      - system:kube-scheduler
      - system:serviceaccount:kube-system:endpoint-controller
    verbs: ["get", "update"]
    namespaces: ["kube-system"]
    resources:
      - group: "" # core
        resources: ["endpoints"]
  - level: None
    users: ["system:apiserver"]
    verbs: ["get"]
    resources:
      - group: "" # core
        resources: ["namespaces", "namespaces/status", "namespaces/finalize"]
  # Don't log HPA fetching metrics.
  - level: None
    users:
      - system:kube-controller-manager
    verbs: ["get", "list"]
    resources:
      - group: "metrics.k8s.io"
  # Don't log these read-only URLs.
  - level: None
    nonResourceURLs:
      - /healthz*
      - /version
      - /swagger*
  # Don't log events requests.
  - level: None
    resources:
      - group: "" # core
        resources: ["events"]

  # new start
  # 忽略所有访问非认证端口的 API，通常是系统组件如 Kube-Controller 等。
  - level: None
    users: ["system:unsecured"]

  # 忽略 kube-admin 的审计日志
  - level: None
    users: ["kube-admin"]
  # 忽略所有资源状态更新的 API need add
  - level: None
    resources:
    - group: "" # core
      resources: ["events", "nodes/status", "pods/status", "services/status"]
    - group: "authorization.k8s.io"
      resources: ["selfsubjectrulesreviews"]
  # 忽略leases need add
  - level: None
    resources:
    - group: "coordination.k8s.io"
      resources: ["leases"]
  - level: Request
    verbs: ["create", "update", "patch", "delete"]
    users: ["kube-admin"]
  #new end

  # Secrets, ConfigMaps, and TokenReviews can contain sensitive & binary data,
  # so only log at the Metadata level.
  - level: Metadata
    resources:
      - group: "" # core
        resources: ["secrets", "configmaps"]
      - group: authentication.k8s.io
        resources: ["tokenreviews"]
    omitStages:
      - "RequestReceived"
  # Get responses can be large; skip them.
  - level: Request
    verbs: ["get", "list", "watch"]
    resources:
      - group: "" # core
      - group: "admissionregistration.k8s.io"
      - group: "apiextensions.k8s.io"
      - group: "apiregistration.k8s.io"
      - group: "apps"
      - group: "authentication.k8s.io"
      - group: "authorization.k8s.io"
      - group: "autoscaling"
      - group: "batch"
      - group: "certificates.k8s.io"
      - group: "extensions"
      - group: "metrics.k8s.io"
      - group: "networking.k8s.io"
      - group: "policy"
      - group: "rbac.authorization.k8s.io"
      - group: "settings.k8s.io"
      - group: "storage.k8s.io"
    omitStages:
      - "RequestReceived"
  # Default level for known APIs
  - level: RequestResponse
    resources:
      - group: "" # core
      - group: "admissionregistration.k8s.io"
      - group: "apiextensions.k8s.io"
      - group: "apiregistration.k8s.io"
      - group: "apps"
      - group: "authentication.k8s.io"
      - group: "authorization.k8s.io"
      - group: "autoscaling"
      - group: "batch"
      - group: "certificates.k8s.io"
      - group: "extensions"
      - group: "metrics.k8s.io"
      - group: "networking.k8s.io"
      - group: "policy"
      - group: "rbac.authorization.k8s.io"
      - group: "settings.k8s.io"
      - group: "storage.k8s.io"
    omitStages:
      - "RequestReceived"
  # Default level for all other requests.
  - level: Metadata
    omitStages:
      - "RequestReceived"

将以上审计日志文件放到 /etc/kubernetes/audit-policy/ 文件夹下，并取名为 apiserver-audit-policy.yaml 。

配置 API 服务器

打开 API 服务器的配置文件 kube-apiserver.yaml，一般会在 /etc/kubernetes/manifests/ 文件夹下，并添加以下配置信息：

这一步操作前请备份 kube-apiserver.yaml，并且备份的文件不能放在 /etc/kubernetes/manifests/ 下，建议放在 /etc/kubernetes/tmp 。

  1. 在 spec.containers.command 下添加命令：

    --audit-log-maxage=30
--audit-log-maxbackup=1
--audit-log-maxsize=100
--audit-log-path=/var/log/audit/kube-apiserver-audit.log
--audit-policy-file=/etc/kubernetes/audit-policy/apiserver-audit-policy.yaml

  2. 在 spec.containers.volumeMounts 下添加：

    - mountPath: /var/log/audit
  name: audit-logs
- mountPath: /etc/kubernetes/audit-policy
  name: audit-policy

  3. 在 spec.volumes 下添加：

    - hostPath:
  path: /var/log/kubernetes/audit
  type: ""
  name: audit-logs
- hostPath:
  path: /etc/kubernetes/audit-policy
  type: ""
  name: audit-policy

测试并验证

稍等一会，API 服务器会自动重启，执行以下命令查看 /var/log/kubernetes/audit 目录下是否有审计日志生成，若有，则表示 k8s 审计日志成功开启。

ls /var/log/kubernetes/audit

如果想关闭，去掉 spec.containers.command 中的相关命令即可。

评论