Collecting Linux Server Metrics with Prometheus

Log in to the LimeDrop web server to perform the following steps.

Create a user and group that will be used to run Node Exporter:

sudo useradd -M -r -s /bin/false node_exporter

Download and extract the Node Exporter binary:

wget https://github.com/prometheus/node_exporter/releases/download/v0.18.1/node_exporter-0.18.1.linux-amd64.tar.gz

tar xvfz node_exporter-0.18.1.linux-amd64.tar.gz

Copy the Node Exporter binary to the appropriate location and set ownership:

sudo cp node_exporter-0.18.1.linux-amd64/node_exporter /usr/local/bin/

sudo chown node_exporter:node_exporter /usr/local/bin/node_exporter

Create a systemd unit file for Node Exporter:

sudo vi /etc/systemd/system/node_exporter.service

Define the Node Exporter service in the unit file:

[Unit]
Description=Prometheus Node Exporter
Wants=network-online.target
After=network-online.target

[Service]
User=node_exporter
Group=node_exporter
Type=simple
ExecStart=/usr/local/bin/node_exporter

[Install]
WantedBy=multi-user.target

Start and enable the service:

sudo systemctl daemon-reload

sudo systemctl start node_exporter

sudo systemctl enable node_exporter

Test that your Node Exporter is working by making a request to it from localhost. You should get some metric data on the screen in response to this request:

curl localhost:9100/metrics

Log in to the Prometheus server to perform the following steps.

Edit the Prometheus config file:

sudo vi /etc/prometheus/prometheus.yml

Locate the scrape_configs section and add a new entry under that section:

...

  - job_name: 'LimeDrop Web Server'
    static_configs:
    - targets: ['10.0.1.102:9100']

...

Restart Prometheus to load the new config:

sudo systemctl restart prometheus

Navigate to the Prometheus expression browser in your web browser using the public IP address of your Prometheus server: <PROMETHEUS_SERVER_PUBLIC_IP>:9090.

Run the following query to verify you are able to get some metric data from the LimeDrop web server:

node_filesystem_avail_bytes{job="LimeDrop Web Server"}