Node Exporter on Prometheus

Configuration guide — Integrating Node Exporter for System Metrics

Introduction

In this article we’ll look at how to add machines that expose system metrics with Node Exporter to the Prometheus log aggregation tool

Prerequisites

• Machines that expose their system metrics using Node Exporter
• Prometheus installed

You’re missing one of the prerequisites? Check my special monitoring list and you’ll find a tutorial on how to do it.

Configuration

Modify the Prometheus configuration file

vim /opt/prometheus/prometheus.yml

Replace the default content with the following

global:
  scrape_interval: 15s
  evaluation_interval: 15s

alerting:
  alertmanagers:
    - static_configs:
        - targets:
rule_files:
scrape_configs:
  - job_name: 'node_exporter'
    file_sd_configs:
      - files:
        - targets.json # Target inventory file
  - job_name: "prometheus-metrics"
    static_configs:
      - targets: ["localhost:9090"]

Add the machines to monitor in the targets file specified in the Prometheus configuration

vim /opt/prometheus/targets.json

[
  {
    "targets": [ "node1:9100", "node2:9100" ],
    "labels": {
      "env": "prod",
      "custom-label": "example"
    }
  },
  {
    "targets": [ "node3:9100" ],
    "labels": {
      "env": "test",
      "custom-label": "example-2"
    }
  }
]

Restart the service

systemctl restart prometheus.service

Check the service status

systemctl status prometheus.service

Result

Go to http://<ip-of-the-machine>:9090/targets and make sure that the target have appeared

Go further

Grafana