Node Exporter

Questo documento descrive come configurare la tua implementazione di Google Kubernetes Engine in modo da poter utilizzare Google Cloud Managed Service per Prometheus per raccogliere le metriche da Node Exporter. Questo documento mostra come eseguire le seguenti operazioni:

  • Configurare Node Exporter per segnalare le metriche.
  • Accedere a una dashboard predefinita in Cloud Monitoring per visualizzare le metriche.
  • Configurare le regole di avviso per monitorare le metriche.

Queste istruzioni si applicano solo se utilizzi la raccolta gestita con Managed Service per Prometheus. Se utilizzi la raccolta con deployment automatico, consulta il repository di origine per Node Exporter per informazioni sull'installazione.

Queste istruzioni sono fornite a titolo di esempio e dovrebbero funzionare nella maggior parte degli ambienti Kubernetes. Se hai difficoltà a installare un'applicazione o un exporter a causa di policy di sicurezza o aziendali restrittive, ti consigliamo di consultare la documentazione open source per ricevere assistenza.

Prerequisiti

Per raccogliere le metriche da Node Exporter utilizzando Managed Service per Prometheus e la raccolta gestita, la tua implementazione deve soddisfare i seguenti requisiti:

Queste metriche sono già abilitate per i nodi nei cluster GKE Autopilot.

Installare Node Exporter

Puoi utilizzare la seguente configurazione per installare Node Exporter:

# Copyright 2022 Google LLC
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
#     https://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.

apiVersion: apps/v1
kind: DaemonSet
metadata:
  namespace: gmp-public
  name: node-exporter
  labels:
    app.kubernetes.io/name: node-exporter
    app.kubernetes.io/version: 1.8.2
spec:
  selector:
    matchLabels:
      app.kubernetes.io/name: node-exporter
  updateStrategy:
    type: RollingUpdate
    rollingUpdate:
      maxUnavailable: 10%
  template:
    metadata:
      labels:
        app.kubernetes.io/name: node-exporter
        app.kubernetes.io/version: 1.8.2
    spec:
      affinity:
        nodeAffinity:
          requiredDuringSchedulingIgnoredDuringExecution:
            nodeSelectorTerms:
            - matchExpressions:
              - key: kubernetes.io/arch
                operator: In
                values:
                - arm64
                - amd64
              - key: kubernetes.io/os
                operator: In
                values:
                - linux
      containers:
      - name: node-exporter
        image: quay.io/prometheus/node-exporter:v1.8.2
        args:
        - --web.listen-address=:8080
        - --path.sysfs=/host/sys
        - --path.rootfs=/host/root
        - --no-collector.wifi
        - --no-collector.hwmon
        - --collector.filesystem.ignored-mount-points=^/(dev|proc|sys|var/lib/docker/.+|var/lib/kubelet/pods/.+)($|/)
        - --collector.netclass.ignored-devices=^(veth.*)$
        - --collector.netdev.device-exclude=^(veth.*)$
        ports:
        - name: metrics
          containerPort: 8080
        resources:
          limits:
            memory: 180Mi
          requests:
            cpu: 102m
            memory: 180Mi
        volumeMounts:
        - mountPath: /host/sys
          mountPropagation: HostToContainer
          name: sys
          readOnly: true
        - mountPath: /host/root
          mountPropagation: HostToContainer
          name: root
          readOnly: true
      hostNetwork: true
      hostPID: true
      securityContext:
        runAsNonRoot: true
        runAsUser: 65534
      volumes:
      - hostPath:
          path: /sys
        name: sys
      - hostPath:
          path: /
        name: root
---
apiVersion: monitoring.googleapis.com/v1
kind: PodMonitoring
metadata:
  namespace: gmp-public
  name: node-exporter
  labels:
    app.kubernetes.io/name: node-exporter
    app.kubernetes.io/part-of: google-cloud-managed-prometheus
spec:
  selector:
    matchLabels:
      app.kubernetes.io/name: node-exporter
  endpoints:
  - port: metrics
    interval: 30s

Per applicare le modifiche alla configurazione da un file locale, esegui il seguente comando: 

kubectl apply -f FILE_NAME

Puoi anche utilizzare Terraform per gestire le configurazioni.

Definire regole e avvisi

Puoi utilizzare la seguente Rules configurazione per definire gli avvisi sulle metriche:

# Copyright 2022 Google LLC
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
#     https://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.

apiVersion: monitoring.googleapis.com/v1
kind: Rules
metadata:
  namespace: gmp-public
  name: node-exporter-rules
  labels:
    app.kubernetes.io/component: rules
    app.kubernetes.io/name: node-exporter-rules
    app.kubernetes.io/part-of: google-cloud-managed-prometheus
spec:
  groups:
  - name: node-exporter
    interval: 30s
    rules:
    - alert: NodeFilesystemSpaceFillingUp
      annotations:
        description: Filesystem on {{ $labels.device }} at {{ $labels.instance }}
          has only {{ printf "%.2f" $value }}% available space left and is filling
          up.
        runbook_url: https://runbooks.prometheus-operator.dev/runbooks/node/nodefilesystemspacefillingup
        summary: Filesystem is predicted to run out of space within the next 24 hours.
      expr: |
        (
          node_filesystem_avail_bytes{job="node-exporter",fstype!=""} / node_filesystem_size_bytes{job="node-exporter",fstype!=""} * 100 < 15
        and
          predict_linear(node_filesystem_avail_bytes{job="node-exporter",fstype!=""}[6h], 24 * 60 * 60) < 0
        and
          node_filesystem_readonly{job="node-exporter",fstype!=""} == 0
        )
      for: 1h
      labels:
        severity: warning
    - alert: NodeFilesystemSpaceFillingUp
      annotations:
        description: Filesystem on {{ $labels.device }} at {{ $labels.instance }}
          has only {{ printf "%.2f" $value }}% available space left and is filling
          up fast.
        runbook_url: https://runbooks.prometheus-operator.dev/runbooks/node/nodefilesystemspacefillingup
        summary: Filesystem is predicted to run out of space within the next 4 hours.
      expr: |
        (
          node_filesystem_avail_bytes{job="node-exporter",fstype!=""} / node_filesystem_size_bytes{job="node-exporter",fstype!=""} * 100 < 10
        and
          predict_linear(node_filesystem_avail_bytes{job="node-exporter",fstype!=""}[6h], 4*60*60) < 0
        and
          node_filesystem_readonly{job="node-exporter",fstype!=""} == 0
        )
      for: 1h
      labels:
        severity: critical
    - alert: NodeFilesystemAlmostOutOfSpace
      annotations:
        description: Filesystem on {{ $labels.device }} at {{ $labels.instance }}
          has only {{ printf "%.2f" $value }}% available space left.
        runbook_url: https://runbooks.prometheus-operator.dev/runbooks/node/nodefilesystemalmostoutofspace
        summary: Filesystem has less than 5% space left.
      expr: |
        (
          node_filesystem_avail_bytes{job="node-exporter",fstype!=""} / node_filesystem_size_bytes{job="node-exporter",fstype!=""} * 100 < 5
        and
          node_filesystem_readonly{job="node-exporter",fstype!=""} == 0
        )
      for: 30m
      labels:
        severity: warning
    - alert: NodeFilesystemAlmostOutOfSpace
      annotations:
        description: Filesystem on {{ $labels.device }} at {{ $labels.instance }}
          has only {{ printf "%.2f" $value }}% available space left.
        runbook_url: https://runbooks.prometheus-operator.dev/runbooks/node/nodefilesystemalmostoutofspace
        summary: Filesystem has less than 3% space left.
      expr: |
        (
          node_filesystem_avail_bytes{job="node-exporter",fstype!=""} / node_filesystem_size_bytes{job="node-exporter",fstype!=""} * 100 < 3
        and
          node_filesystem_readonly{job="node-exporter",fstype!=""} == 0
        )
      for: 30m
      labels:
        severity: critical
    - alert: NodeFilesystemFilesFillingUp
      annotations:
        description: Filesystem on {{ $labels.device }} at {{ $labels.instance }}
          has only {{ printf "%.2f" $value }}% available inodes left and is filling
          up.
        runbook_url: https://runbooks.prometheus-operator.dev/runbooks/node/nodefilesystemfilesfillingup
        summary: Filesystem is predicted to run out of inodes within the next 24 hours.
      expr: |
        (
          node_filesystem_files_free{job="node-exporter",fstype!=""} / node_filesystem_files{job="node-exporter",fstype!=""} * 100 < 40
        and
          predict_linear(node_filesystem_files_free{job="node-exporter",fstype!=""}[6h], 24*60*60) < 0
        and
          node_filesystem_readonly{job="node-exporter",fstype!=""} == 0
        )
      for: 1h
      labels:
        severity: warning
    - alert: NodeFilesystemFilesFillingUp
      annotations:
        description: Filesystem on {{ $labels.device }} at {{ $labels.instance }}
          has only {{ printf "%.2f" $value }}% available inodes left and is filling
          up fast.
        runbook_url: https://runbooks.prometheus-operator.dev/runbooks/node/nodefilesystemfilesfillingup
        summary: Filesystem is predicted to run out of inodes within the next 4 hours.
      expr: |
        (
          node_filesystem_files_free{job="node-exporter",fstype!=""} / node_filesystem_files{job="node-exporter",fstype!=""} * 100 < 20
        and
          predict_linear(node_filesystem_files_free{job="node-exporter",fstype!=""}[6h], 4*60*60) < 0
        and
          node_filesystem_readonly{job="node-exporter",fstype!=""} == 0
        )
      for: 1h
      labels:
        severity: critical
    - alert: NodeFilesystemAlmostOutOfFiles
      annotations:
        description: Filesystem on {{ $labels.device }} at {{ $labels.instance }}
          has only {{ printf "%.2f" $value }}% available inodes left.
        runbook_url: https://runbooks.prometheus-operator.dev/runbooks/node/nodefilesystemalmostoutoffiles
        summary: Filesystem has less than 5% inodes left.
      expr: |
        (
          node_filesystem_files_free{job="node-exporter",fstype!=""} / node_filesystem_files{job="node-exporter",fstype!=""} * 100 < 5
        and
          node_filesystem_readonly{job="node-exporter",fstype!=""} == 0
        )
      for: 1h
      labels:
        severity: warning
    - alert: NodeFilesystemAlmostOutOfFiles
      annotations:
        description: Filesystem on {{ $labels.device }} at {{ $labels.instance }}
          has only {{ printf "%.2f" $value }}% available inodes left.
        runbook_url: https://runbooks.prometheus-operator.dev/runbooks/node/nodefilesystemalmostoutoffiles
        summary: Filesystem has less than 3% inodes left.
      expr: |
        (
          node_filesystem_files_free{job="node-exporter",fstype!=""} / node_filesystem_files{job="node-exporter",fstype!=""} * 100 < 3
        and
          node_filesystem_readonly{job="node-exporter",fstype!=""} == 0
        )
      for: 1h
      labels:
        severity: critical
    - alert: NodeNetworkReceiveErrs
      annotations:
        description: '{{ $labels.instance }} interface {{ $labels.device }} has encountered
          {{ printf "%.0f" $value }} receive errors in the last two minutes.'
        runbook_url: https://runbooks.prometheus-operator.dev/runbooks/node/nodenetworkreceiveerrs
        summary: Network interface is reporting many receive errors.
      expr: |
        rate(node_network_receive_errs_total[2m]) / rate(node_network_receive_packets_total[2m]) > 0.01
      for: 1h
      labels:
        severity: warning
    - alert: NodeNetworkTransmitErrs
      annotations:
        description: '{{ $labels.instance }} interface {{ $labels.device }} has encountered
          {{ printf "%.0f" $value }} transmit errors in the last two minutes.'
        runbook_url: https://runbooks.prometheus-operator.dev/runbooks/node/nodenetworktransmiterrs
        summary: Network interface is reporting many transmit errors.
      expr: |
        rate(node_network_transmit_errs_total[2m]) / rate(node_network_transmit_packets_total[2m]) > 0.01
      for: 1h
      labels:
        severity: warning
    - alert: NodeHighNumberConntrackEntriesUsed
      annotations:
        description: '{{ $value | humanizePercentage }} of conntrack entries are used.'
        runbook_url: https://runbooks.prometheus-operator.dev/runbooks/node/nodehighnumberconntrackentriesused
        summary: Number of conntrack are getting close to the limit.
      expr: |
        (node_nf_conntrack_entries / node_nf_conntrack_entries_limit) > 0.75
      labels:
        severity: warning
    - alert: NodeTextFileCollectorScrapeError
      annotations:
        description: Node Exporter text file collector failed to scrape.
        runbook_url: https://runbooks.prometheus-operator.dev/runbooks/node/nodetextfilecollectorscrapeerror
        summary: Node Exporter text file collector failed to scrape.
      expr: |
        node_textfile_scrape_error{job="node-exporter"} == 1
      labels:
        severity: warning
    - alert: NodeClockSkewDetected
      annotations:
        description: Clock on {{ $labels.instance }} is out of sync by more than 300s.
          Ensure NTP is configured correctly on this host.
        runbook_url: https://runbooks.prometheus-operator.dev/runbooks/node/nodeclockskewdetected
        summary: Clock skew detected.
      expr: |
        (
          node_timex_offset_seconds{job="node-exporter"} > 0.05
        and
          deriv(node_timex_offset_seconds{job="node-exporter"}[5m]) >= 0
        )
        or
        (
          node_timex_offset_seconds{job="node-exporter"} < -0.05
        and
          deriv(node_timex_offset_seconds{job="node-exporter"}[5m]) <= 0
        )
      for: 10m
      labels:
        severity: warning
    - alert: NodeClockNotSynchronising
      annotations:
        description: Clock on {{ $labels.instance }} is not synchronising. Ensure
          NTP is configured on this host.
        runbook_url: https://runbooks.prometheus-operator.dev/runbooks/node/nodeclocknotsynchronising
        summary: Clock not synchronising.
      expr: |
        min_over_time(node_timex_sync_status{job="node-exporter"}[5m]) == 0
        and
        node_timex_maxerror_seconds{job="node-exporter"} >= 16
      for: 10m
      labels:
        severity: warning
    - alert: NodeRAIDDegraded
      annotations:
        description: RAID array '{{ $labels.device }}' on {{ $labels.instance }} is
          in degraded state due to one or more disks failures. Number of spare drives
          is insufficient to fix issue automatically.
        runbook_url: https://runbooks.prometheus-operator.dev/runbooks/node/noderaiddegraded
        summary: RAID Array is degraded
      expr: |
        node_md_disks_required{job="node-exporter",device=~"(/dev/)?(mmcblk.p.+|nvme.+|rbd.+|sd.+|vd.+|xvd.+|dm-.+|dasd.+)"} - ignoring (state) (node_md_disks{state="active",job="node-exporter",device=~"(/dev/)?(mmcblk.p.+|nvme.+|rbd.+|sd.+|vd.+|xvd.+|dm-.+|dasd.+)"}) > 0
      for: 15m
      labels:
        severity: critical
    - alert: NodeRAIDDiskFailure
      annotations:
        description: At least one device in RAID array on {{ $labels.instance }} failed.
          Array '{{ $labels.device }}' needs attention and possibly a disk swap.
        runbook_url: https://runbooks.prometheus-operator.dev/runbooks/node/noderaiddiskfailure
        summary: Failed device in RAID array
      expr: |
        node_md_disks{state="failed",job="node-exporter",device=~"(/dev/)?(mmcblk.p.+|nvme.+|rbd.+|sd.+|vd.+|xvd.+|dm-.+|dasd.+)"} > 0
      labels:
        severity: warning
    - alert: NodeFileDescriptorLimit
      annotations:
        description: File descriptors limit at {{ $labels.instance }} is currently
          at {{ printf "%.2f" $value }}%.
        runbook_url: https://runbooks.prometheus-operator.dev/runbooks/node/nodefiledescriptorlimit
        summary: Kernel is predicted to exhaust file descriptors limit soon.
      expr: |
        (
          node_filefd_allocated{job="node-exporter"} * 100 / node_filefd_maximum{job="node-exporter"} > 70
        )
      for: 15m
      labels:
        severity: warning
    - alert: NodeFileDescriptorLimit
      annotations:
        description: File descriptors limit at {{ $labels.instance }} is currently
          at {{ printf "%.2f" $value }}%.
        runbook_url: https://runbooks.prometheus-operator.dev/runbooks/node/nodefiledescriptorlimit
        summary: Kernel is predicted to exhaust file descriptors limit soon.
      expr: |
        (
          node_filefd_allocated{job="node-exporter"} * 100 / node_filefd_maximum{job="node-exporter"} > 90
        )
      for: 15m
      labels:
        severity: critical
  - name: node-exporter.rules
    interval: 30s
    rules:
    - expr: |
        count without (cpu, mode) (
          node_cpu_seconds_total{job="node-exporter",mode="idle"}
        )
      record: instance:node_num_cpu:sum
    - expr: |
        1 - avg without (cpu) (
          sum without (mode) (rate(node_cpu_seconds_total{job="node-exporter", mode=~"idle|iowait|steal"}[5m]))
        )
      record: instance:node_cpu_utilisation:rate5m
    - expr: |
        (
          node_load1{job="node-exporter"}
        /
          instance:node_num_cpu:sum{job="node-exporter"}
        )
      record: instance:node_load1_per_cpu:ratio
    - expr: |
        1 - (
          (
            node_memory_MemAvailable_bytes{job="node-exporter"}
            or
            (
              node_memory_Buffers_bytes{job="node-exporter"}
              +
              node_memory_Cached_bytes{job="node-exporter"}
              +
              node_memory_MemFree_bytes{job="node-exporter"}
              +
              node_memory_Slab_bytes{job="node-exporter"}
            )
          )
        /
          node_memory_MemTotal_bytes{job="node-exporter"}
        )
      record: instance:node_memory_utilisation:ratio
    - expr: |
        rate(node_vmstat_pgmajfault{job="node-exporter"}[5m])
      record: instance:node_vmstat_pgmajfault:rate5m
    - expr: |
        rate(node_disk_io_time_seconds_total{job="node-exporter", device=~"(/dev/)?(mmcblk.p.+|nvme.+|rbd.+|sd.+|vd.+|xvd.+|dm-.+|dasd.+)"}[5m])
      record: instance_device:node_disk_io_time_seconds:rate5m
    - expr: |
        rate(node_disk_io_time_weighted_seconds_total{job="node-exporter", device=~"(/dev/)?(mmcblk.p.+|nvme.+|rbd.+|sd.+|vd.+|xvd.+|dm-.+|dasd.+)"}[5m])
      record: instance_device:node_disk_io_time_weighted_seconds:rate5m
    - expr: |
        sum without (device) (
          rate(node_network_receive_bytes_total{job="node-exporter", device!="lo"}[5m])
        )
      record: instance:node_network_receive_bytes_excluding_lo:rate5m
    - expr: |
        sum without (device) (
          rate(node_network_transmit_bytes_total{job="node-exporter", device!="lo"}[5m])
        )
      record: instance:node_network_transmit_bytes_excluding_lo:rate5m
    - expr: |
        sum without (device) (
          rate(node_network_receive_drop_total{job="node-exporter", device!="lo"}[5m])
        )
      record: instance:node_network_receive_drop_excluding_lo:rate5m
    - expr: |
        sum without (device) (
          rate(node_network_transmit_drop_total{job="node-exporter", device!="lo"}[5m])
        )
      record: instance:node_network_transmit_drop_excluding_lo:rate5m

Per applicare le modifiche alla configurazione da un file locale, esegui il seguente comando: 

kubectl apply -f FILE_NAME

Puoi anche utilizzare Terraform per gestire le configurazioni.

Per maggiori informazioni sull'applicazione delle regole al cluster, consulta Valutazione e avvisi delle regole gestite.

Questa configurazione Rules è stata adattata dalle regole e dagli avvisi forniti al repository kube-prometheus.

Verificare la configurazione

Puoi utilizzare Metrics Explorer per verificare di aver configurato correttamente Node Exporter. Cloud Monitoring potrebbe richiedere uno o due minuti per inserire le metriche.

Per verificare che le metriche siano inserite:

  1. Nella Google Cloud console, vai alla  Esplora metriche pagina:

    Vai a Esplora metriche

    Se utilizzi la barra di ricerca per trovare questa pagina, seleziona il risultato con il sottotitolo Monitoring.

  2. Nella barra degli strumenti del riquadro del generatore di query, seleziona il pulsante il cui nome è  PromQL.
  3. Inserisci ed esegui la seguente query:
    up{job="node-exporter", cluster="CLUSTER_NAME", namespace="gmp-public"}

Installare le dashboard

Cloud Monitoring fornisce una libreria di dashboard di esempio per le integrazioni. La libreria di esempi include le dashboard "Prometheus", che puoi installare per visualizzare i tuoi dati nella Google Cloud console.

Tieni presente che la dashboard Panoramica di Prometheus del cluster Kubernetes richiede l'installazione di Kube State Metrics. La dashboard Panoramica di Prometheus del pod Kubernetes richiede l'installazione di Kube State Metrics e Kubelet/cAdvisor.

Per installare una dashboard dalla libreria di esempi:

  1. Nella Google Cloud console, vai alla pagina  Dashboard:

    Vai a Dashboard

    Se utilizzi la barra di ricerca per trovare questa pagina, seleziona il risultato con il sottotitolo Monitoring.

  2. Seleziona la scheda Libreria di esempi.
  3. Scegli la categoria Altro.
  4. (Facoltativo) Per visualizzare un'anteprima statica di una dashboard senza installarla, fai clic su Anteprima.
  5. Seleziona le dashboard che vuoi installare, quindi fai clic su download Importa.

Per maggiori informazioni sull'installazione delle dashboard, consulta Installare le dashboard di esempio.

Risoluzione dei problemi

Per informazioni sulla risoluzione dei problemi di inserimento delle metriche, consulta Problemi con la raccolta dagli exporter in Risolvere i problemi di inserimento.