🥇Prometheus: HTTP-monitering via Blackbox-uitvoerder

Hi almal. In Mei word OTUS bekendgestel werkswinkel oor monitering en aantekening, beide infrastruktuur en toepassings wat Zabbix, Prometheus, Grafana en ELK gebruik. In hierdie verband deel ons tradisioneel nuttige materiaal oor die onderwerp.

Blackbox uitvoerder vir Prometheus laat jou toe om eksterne dienste te monitor via HTTP, HTTPS, DNS, TCP, ICMP. In hierdie artikel sal ek jou wys hoe om HTTP/HTTPS-monitering op te stel met behulp van die Blackbox-uitvoerder. Ons sal die Blackbox-uitvoerder in Kubernetes bedryf.

Die omgewing

Ons sal die volgende nodig hê:

Kubernetes
Prometheus-operateur

blackbox uitvoerder konfigurasie

Konfigureer Blackbox via ConfigMap vir instellings http webdienste-moniteringsmodule.

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 word gebruik om te verifieer dat die webdiens 'n 2xx HTTP-statuskode terugstuur. Die konfigurasie van die blackbox-uitvoerder word in meer besonderhede beskryf in dokumentasie.

Ontplooi blackbox-uitvoerder na Kubernetes-groepering

Beskryf Deployment и Service vir ontplooiing in 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

Die Blackbox-uitvoerder kan met die volgende opdrag ontplooi word. Naamruimte monitoring verwys na die Prometheus-operateur.

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

Verifieer dat alle dienste loop met die volgende opdrag:

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

Blackbox-tjek

Jy kan toegang kry tot die Blackbox Exporter-webkoppelvlak met port-forward:

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

Koppel aan die Blackbox Exporter-webkoppelvlak deur 'n webblaaier by localhost: 9115.

As jy gaan na http://localhost:9115/probe?module=http_2xx&target=https://www.google.com, sal jy die resultaat sien van die nagaan van die gespesifiseerde URL (https://www.google.com).

Metrieke waarde probe_success gelyk aan 1 beteken suksesvolle tjek. 'n Waarde van 0 dui op 'n fout.

Die opstel van Prometheus

Nadat u die BlackBox-uitvoerder ontplooi het, stel Prometheus in 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.

Ons genereer Secretmet behulp van die volgende opdrag.

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

Ons dui aan additional-scrape-configs vir Prometheus Operator gebruik additionalScrapeConfigs.

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

Ons gaan na die Prometheus-webkoppelvlak, kyk na die maatstawwe en doelwitte.

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

Ons sien die maatstawwe en doelwitte van Blackbox.

Voeg reëls vir kennisgewings by (waarskuwing)

Om waarskuwings van die Blackbox-uitvoerder te ontvang, kom ons voeg reëls by die 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 }}"

In die Prometheus-webkoppelvlak, gaan na Status => Reëls en vind die waarskuwingsreëls vir die blackbox-uitvoerder.

Konfigureer Kubernetes API Server SSL-sertifikaatvervalkennisgewings

Kom ons stel Kubernetes API Server SSL-sertifikaatvervalmonitering op. Dit sal een keer per week kennisgewings stuur.

Voeg die Blackbox-uitvoerdermodule by vir 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

Voeg die Prometheus-skraapkonfigurasie by

- 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.

Pas Prometheus Secret toe

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

Voeg waarskuwingsreëls by

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 skakels

Monitering en aanteken in Docker

Bron: will.com