👨🏼‍🔬 😑 ♠️ Prometheus：通过Blackbox导出程序进行HTTP监视 💅🏻 👾 💹

大家好。5月，OTUS 使用Zabbix，Prometheus，Grafana和ELK 启动了有关基础结构和应用程序的监视和日志记录的研讨会。在这方面，我们传统上共享有关该主题的有用材料。

用于Prometheus的Blackbox导出程序允许您通过HTTP，HTTPS，DNS，TCP，ICMP监视外部服务。在本文中，我将向您展示如何使用Blackbox导出程序配置HTTP / HTTPS监视。我们将在Kubernetes中启动Blackbox导出程序。

环境

我们将需要以下内容：

Kubernetes
普罗米修斯算子

黑盒导出器配置

我们通过配置Blackbox ConfigMap来配置httpWeb服务监视模块。

apiVersion: v1
kind: ConfigMap
metadata:
  name: prometheus-blackbox-exporter
  labels:
    app: prometheus-blackbox-exporter
data:
  blackbox.yaml: |
    modules:
      http_2xx:
        http:
          no_follow_redirects: false
          preferred_ip_protocol: ip4
          valid_http_versions:
          - HTTP/1.1
          - HTTP/2
          valid_status_codes: []
        prober: http
        timeout: 5s

该模块http_2xx用于验证Web服务是否返回HTTP 2xx状态代码。黑匣子导出器的配置在文档中有更详细的描述。

在Kubernetes集群中部署黑盒导出器

描述Deployment并Service在Kubernetes中进行部署。

---
kind: Service
apiVersion: v1
metadata:
  name: prometheus-blackbox-exporter
  labels:
    app: prometheus-blackbox-exporter
spec:
  type: ClusterIP
  ports:
    - name: http
      port: 9115
      protocol: TCP
  selector:
    app: prometheus-blackbox-exporter

---
apiVersion: apps/v1
kind: Deployment
metadata:
  name: prometheus-blackbox-exporter
  labels:
    app: prometheus-blackbox-exporter
spec:
  replicas: 1
  selector:
    matchLabels:
      app: prometheus-blackbox-exporter
  template:
    metadata:
      labels:
        app: prometheus-blackbox-exporter
    spec:
      restartPolicy: Always
      containers:
        - name: blackbox-exporter
          image: "prom/blackbox-exporter:v0.15.1"
          imagePullPolicy: IfNotPresent
          securityContext:
            readOnlyRootFilesystem: true
            runAsNonRoot: true
            runAsUser: 1000
          args:
            - "--config.file=/config/blackbox.yaml"
          resources:
            {}
          ports:
            - containerPort: 9115
              name: http
          livenessProbe:
            httpGet:
              path: /health
              port: http
          readinessProbe:
            httpGet:
              path: /health
              port: http
          volumeMounts:
            - mountPath: /config
              name: config
        - name: configmap-reload
          image: "jimmidyson/configmap-reload:v0.2.2"
          imagePullPolicy: "IfNotPresent"
          securityContext:
            runAsNonRoot: true
            runAsUser: 65534
          args:
            - --volume-dir=/etc/config
            - --webhook-url=http://localhost:9115/-/reload
          resources:
            {}
          volumeMounts:
            - mountPath: /etc/config
              name: config
              readOnly: true
      volumes:
        - name: config
          configMap:
            name: prometheus-blackbox-exporter

可以使用以下命令部署黑盒导出器。名称空间monitoring是指Prometheus运算符。

kubectl --namespace=monitoring apply -f blackbox-exporter.yaml

使用以下命令验证所有服务都在运行：

kubectl --namespace=monitoring get all --selector=app=prometheus-blackbox-exporter

检查黑匣子

您可以使用以下命令访问导出程序Blackbox Web界面port-forward：

kubectl --namespace=monitoring port-forward svc/prometheus-blackbox-exporter 9115:9115

通过位于localhost：9115 的Web浏览器连接到导出器的Blackbox Web界面。

如果您转到地址http：//本地主机：9115 / probe？Module = http_2xx＆target = https：//www.google.com，则会看到检查指定URL（https://www.google.com）的结果。

度量标准probe_success值1表示检查成功。值为0表示错误。

设置普罗米修斯

部署BlackBox导出器后，配置Prometheus prometheus-additional.yaml。

- job_name: 'kube-api-blackbox'
  scrape_interval: 1w
  metrics_path: /probe
  params:
    module: [http_2xx]
  static_configs:
   - targets:
      - https://www.google.com
      - http://www.example.com
      - https://prometheus.io
  relabel_configs:
   - source_labels: [__address__]
     target_label: __param_target
   - source_labels: [__param_target]
     target_label: instance
   - target_label: __address__
     replacement: prometheus-blackbox-exporter:9115 # The blackbox exporter.

Secret使用以下命令生成。

PROMETHEUS_ADD_CONFIG=$(cat prometheus-additional.yaml | base64)
cat << EOF | kubectl --namespace=monitoring apply -f -
apiVersion: v1
kind: Secret
metadata:
  name: additional-scrape-configs
type: Opaque
data:
  prometheus-additional.yaml: $PROMETHEUS_ADD_CONFIG
EOF

使用来指定additional-scrape-configsPrometheus运算符additionalScrapeConfigs。

kubectl --namespace=monitoring edit prometheuses k8s
...
spec:
  additionalScrapeConfigs:
    key: prometheus-additional.yaml
    name: additional-scrape-configs

我们进入Prometheus Web界面，检查指标和目标。

kubectl --namespace=monitoring port-forward svc/prometheus-k8s 9090:9090

我们看到了黑匣子的指标和目标。

添加通知规则（警报）

要从Blackbox导出器接收通知，请将规则添加到Prometheus Operator。

kubectl --namespace=monitoring edit prometheusrules prometheus-k8s-rules
...
  - name: blackbox-exporter
    rules:
    - alert: ProbeFailed
      expr: probe_success == 0
      for: 5m
      labels:
        severity: error
      annotations:
        summary: "Probe failed (instance {{ $labels.instance }})"
        description: "Probe failed\n  VALUE = {{ $value }}\n  LABELS: {{ $labels }}"
    - alert: SlowProbe
      expr: avg_over_time(probe_duration_seconds[1m]) > 1
      for: 5m
      labels:
        severity: warning
      annotations:
        summary: "Slow probe (instance {{ $labels.instance }})"
        description: "Blackbox probe took more than 1s to complete\n  VALUE = {{ $value }}\n  LABELS: {{ $labels }}"
    - alert: HttpStatusCode
      expr: probe_http_status_code <= 199 OR probe_http_status_code >= 400
      for: 5m
      labels:
        severity: error
      annotations:
        summary: "HTTP Status Code (instance {{ $labels.instance }})"
        description: "HTTP status code is not 200-399\n  VALUE = {{ $value }}\n  LABELS: {{ $labels }}"
    - alert: SslCertificateWillExpireSoon
      expr: probe_ssl_earliest_cert_expiry - time() < 86400 * 30
      for: 5m
      labels:
        severity: warning
      annotations:
        summary: "SSL certificate will expire soon (instance {{ $labels.instance }})"
        description: "SSL certificate expires in 30 days\n  VALUE = {{ $value }}\n  LABELS: {{ $labels }}"
    - alert: SslCertificateHasExpired
      expr: probe_ssl_earliest_cert_expiry - time()  <= 0
      for: 5m
      labels:
        severity: error
      annotations:
        summary: "SSL certificate has expired (instance {{ $labels.instance }})"
        description: "SSL certificate has expired already\n  VALUE = {{ $value }}\n  LABELS: {{ $labels }}"
    - alert: HttpSlowRequests
      expr: avg_over_time(probe_http_duration_seconds[1m]) > 1
      for: 5m
      labels:
        severity: warning
      annotations:
        summary: "HTTP slow requests (instance {{ $labels.instance }})"
        description: "HTTP request took more than 1s\n  VALUE = {{ $value }}\n  LABELS: {{ $labels }}"
    - alert: SlowPing
      expr: avg_over_time(probe_icmp_duration_seconds[1m]) > 1
      for: 5m
      labels:
        severity: warning
      annotations:
        summary: "Slow ping (instance {{ $labels.instance }})"
        description: "Blackbox ping took more than 1s\n  VALUE = {{ $value }}\n  LABELS: {{ $labels }}"

在Prometheus Web界面中，转到Status => Rules，然后找到blackbox-exporter的警报规则。

配置Kubernetes API Server SSL证书到期通知

让我们设置监控Kubernetes API Server SSL证书的到期时间。他将每周发送一次通知。

添加用于Kubernetes API服务器身份验证的Blackbox导出器模块。

kubectl --namespace=monitoring edit configmap prometheus-blackbox-exporter
...
      kube-api:
        http:
          method: GET
          no_follow_redirects: false
          preferred_ip_protocol: ip4
          tls_config:
            insecure_skip_verify: false
            ca_file: /var/run/secrets/kubernetes.io/serviceaccount/ca.crt
          bearer_token_file: /var/run/secrets/kubernetes.io/serviceaccount/token
          valid_http_versions:
          - HTTP/1.1
          - HTTP/2
          valid_status_codes: []
        prober: http
        timeout: 5s

添加Prometheus抓取配置

- job_name: 'kube-api-blackbox'
  metrics_path: /probe
  params:
    module: [kube-api]
  static_configs:
   - targets:
      - https://kubernetes.default.svc/api
  relabel_configs:
   - source_labels: [__address__]
     target_label: __param_target
   - source_labels: [__param_target]
     target_label: instance
   - target_label: __address__
     replacement: prometheus-blackbox-exporter:9115 # The blackbox exporter.

应用普罗米修斯秘密

PROMETHEUS_ADD_CONFIG=$(cat prometheus-additional.yaml | base64)
cat << EOF | kubectl --namespace=monitoring apply -f -
apiVersion: v1
kind: Secret
metadata:
  name: additional-scrape-configs
type: Opaque
data:
  prometheus-additional.yaml: $PROMETHEUS_ADD_CONFIG
EOF

添加警报规则

kubectl --namespace=monitoring edit prometheusrules prometheus-k8s-rules
...
  - name: k8s-api-server-cert-expiry
    rules:
    - alert: K8sAPIServerSSLCertExpiringAfterThreeMonths
      expr: probe_ssl_earliest_cert_expiry{job="kube-api-blackbox"} - time() < 86400 * 90 
      for: 1w
      labels:
        severity: warning
      annotations:
        summary: "Kubernetes API Server SSL certificate will expire after three months (instance {{ $labels.instance }})"
        description: "Kubernetes API Server SSL certificate expires in 90 days\n  VALUE = {{ $value }}\n  LABELS: {{ $labels }}"

有用的链接

监控和登录Docker

Prometheus：通过Blackbox导出程序进行HTTP监视

环境