开启/关闭 K8s 审计日志的输出¶

默认 Kubernetes 集群不会输出审计日志信息。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。

准备审计日志的 Policy 文件
配置 API 服务器，开启审计日志
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 。

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

在 spec.containers.volumeMounts 下添加：

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

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。