Monitoring Linux host metrics with the Node Exporter

    In this guide, you will:

    • Start up a Node Exporter on
    • Start up a Prometheus instance on localhost that’s configured to scrape metrics from the running Node Exporter

    NOTE: While the Prometheus Node Exporter is for *nix systems, there is the Windows exporter for Windows that serves an analogous purpose.

    The Prometheus Node Exporter is a single static binary that you can install . Once you’ve downloaded it from the Prometheus downloads page extract it, and run it:

    You should see output like this indicating that the Node Exporter is now running and exposing metrics on port 9100:

    1. INFO[0000] Starting node_exporter (version=0.16.0, branch=HEAD, revision=d42bd70f4363dced6b77d8fc311ea57b63387e4f)  source="node_exporter.go:82"
    2. INFO[0000] Build context (go=go1.9.6, [email protected], date=20180515-15:53:28)  source="node_exporter.go:83"
    3. INFO[0000]  - boottime                                   source="node_exporter.go:97"
    4. ...
    5. INFO[0000] Listening on :9100                            source="node_exporter.go:111"

    You should see output like this:

    1. # HELP go_gc_duration_seconds A summary of the GC invocation durations.
    2. # TYPE go_gc_duration_seconds summary
    4. go_gc_duration_seconds{quantile="0.25"} 4.5926e-05
    5. go_gc_duration_seconds{quantile="0.5"} 5.846e-05

    Success! The Node Exporter is now exposing metrics that Prometheus can scrape, including a wide variety of system metrics further down in the output (prefixed with node_). To view those metrics (along with help and type information):

    Your locally running Prometheus instance needs to be properly configured in order to access Node Exporter metrics. The following example configuration file will tell the Prometheus instance to scrape, and how frequently, from the Node Exporter via localhost:9100:

    1. global:
    2.   scrape_interval: 15s
    4. scrape_configs:
    6.   static_configs:
    7.   - targets: ['localhost:9100']

    To install Prometheus, download the latest release for your platform and untar it:

    1. ./prometheus --config.file=./prometheus.yml

    Now that Prometheus is scraping metrics from a running Node Exporter instance, you can explore those metrics using the Prometheus UI (aka the ). Navigate to localhost:9090/graph in your browser and use the main expression bar at the top of the page to enter expressions. The expression bar looks like this:

    Metrics specific to the Node Exporter are prefixed with node_ and include metrics like node_cpu_seconds_total and node_exporter_build_info.

    Click on the links below to see some example metrics: