🥇Prometheus: HTTP-monitoring fia Blackbox-eksporteur

Hoi allegearre. Yn maaie lansearret OTUS workshop oer tafersjoch en logging, sawol ynfrastruktuer as applikaasjes mei Zabbix, Prometheus, Grafana en ELK. Yn dit ferbân diele wy tradisjoneel brûkber materiaal oer it ûnderwerp.

Blackbox eksporteur foar Prometheus kinne jo tafersjoch op eksterne tsjinsten útfiere fia HTTP, HTTPS, DNS, TCP, ICMP. Yn dit artikel sil ik jo sjen litte hoe't jo HTTP / HTTPS-monitoring ynstelle kinne mei Blackbox-eksporteur. Wy sille de Blackbox-eksporteur yn Kubernetes lansearje.

Miljeu

Wy sille it folgjende nedich wêze:

Kubernetes
Prometheus Operator

Eksporter blackbox konfiguraasje

Blackbox konfigurearje fia ConfigMap foar ynstellings http web tsjinsten monitoring module.

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

Module http_2xx brûkt om te kontrolearjen dat de webtsjinst in HTTP 2xx-statuskoade weromjout. De konfiguraasje fan 'e blackbox-eksporteur wurdt yn mear detail beskreaun yn dokumintaasje.

It ynsetten fan in blackbox-eksporteur nei in Kubernetes-kluster

Beskriuwe Deployment и Service foar ynset yn Kubernetes.

---
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

Blackbox-eksporteur kin wurde ynset mei it folgjende kommando. Nammeromte monitoring ferwiist nei Prometheus Operator.

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

Soargje derfoar dat alle tsjinsten rinne mei it folgjende kommando:

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

Blackbox kontrôle

Jo kinne tagong krije ta de Blackbox-eksporteur-webynterface mei port-forward:

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

Ferbine mei de Blackbox eksporter web ynterface fia in webblêder by localhost: 9115.

As jo nei it adres gean http://localhost:9115/probe?module=http_2xx&target=https://www.google.com, sille jo it resultaat sjen fan it kontrolearjen fan de opjûne URL (https://www.google.com).

Metryske wearde probe_success lyk oan 1 betsjut suksesfol kontrôle. In wearde fan 0 jout in flater oan.

Prometheus ynstelle

Nei it ynsetten fan de BlackBox-eksporteur konfigurearje wy Prometheus yn 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.

Wy generearje Secretmei help fan it folgjende kommando.

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

Wy jouwe oan additional-scrape-configs foar Prometheus Operator brûke additionalScrapeConfigs.

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

Wy geane nei de Prometheus-webynterface en kontrolearje de metriken en doelen.

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

Wy sjogge de metriken en doelen fan Blackbox.

Regels tafoegje foar notifikaasjes (alarm)

Om notifikaasjes te ûntfangen fan 'e Blackbox-eksporteur, sille wy regels tafoegje oan 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 failedn  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 completen  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 200-399n  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 daysn  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 alreadyn  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 1sn  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 1sn  VALUE = {{ $value }}n  LABELS: {{ $labels }}"

Gean yn 'e Prometheus-webynterface nei Status => Regels en fyn de warskôgingsregels foar blackbox-eksporteur.

Konfigurearje Kubernetes API Server SSL Certificate Expiration Notifications

Litte wy Kubernetes API Server SSL-sertifikaat ferfalmonitoring ynstelle. It sil ien kear yn 'e wike notifikaasjes stjoere.

It tafoegjen fan de Blackbox eksporter module foar Kubernetes API Server Authentication.

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

Taheakjen fan Prometheus scrape konfiguraasje

- 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.

It brûken fan Prometheus Secret

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

Alarmregels tafoegje

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 daysn  VALUE = {{ $value }}n  LABELS: {{ $labels }}"

Nuttige keppelings

Monitoring en oanmelde yn Docker

Boarne: www.habr.com