June 28, 2020 3 min to read

Prometheus Node Exporter on AWS EC2

In the previous topic we installed Prometheus and now is ready to receive metrics. The next step is to launch a second AWS EC2 instance, install Prometheus Node Exporter in it and finally, configure Prometheus to collect its metrics.

To continue reading follow these links:

• Install Prometheus on AWS EC2
• Prometheus Node Exporter on AWS EC2
• Prometheus Discovery Service on AWS EC2
• Prometheus Alertmanager Sending Emails

Prometheus Node Exporter

There are many exporters and integrations available for Prometheus. As mentioned above, in this example we are going to install Prometheus Node Exporter in an AWS EC2 instance.

“Prometheus exporter for hardware and OS metrics exposed by *NIX kernels, written in Go with pluggable metric collectors.”

Setup an EC2 Machine

The instructions are similar to the steps we followed to create a Prometheus EC2 instance with some light differences.

One of these differences is that we don’t need to create a new Key Pair since we already created one for Prometheus, as long we have this key safely stored we can choose it from the drop down.

The second difference is that we also don’t need to create a Security Group since we already created one with all the inbound and outbound rules defined for Prometheus and for the Node Exporter.

Installation

Now we should have two AWS EC2 instances created, one Security group and one ssh key for both machines. In your case it will be different but I got the following:

• We need to start a session in the new virtual machine.

ssh -i prometheus.pem ubuntu@ec2-13-58-127-241.us-east-2.compute.amazonaws.com

• Now let’s create a user for Prometheus Node Exporter

sudo useradd --no-create-home node_exporter

• We are ready to install Node Exporter binaries.

wget https://github.com/prometheus/node_exporter/releases/download/v1.0.1/node_exporter-1.0.1.linux-amd64.tar.gz
tar xzf node_exporter-1.0.1.linux-amd64.tar.gz
sudo cp node_exporter-1.0.1.linux-amd64/node_exporter /usr/local/bin/node_exporter
rm -rf node_exporter-1.0.1.linux-amd64.tar.gz node_exporter-1.0.1.linux-amd64

• Configure a service. Create /etc/systemd/system/node-exporter.service if it doesn’t exist.

[Unit]
Description=Prometheus Node Exporter Service
After=network.target

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

[Install]
WantedBy=multi-user.target

• Configure systemd.

  sudo systemctl daemon-reload
  sudo systemctl enable node-exporter
  sudo systemctl start node-exporter
  sudo systemctl status node-exporter
  

Configure Prometheus Server

Now we need to go back to the first AWS EC2 instance where we installed Prometheus and change its configuration to start receiving metrics from the Node Exporter we just installed and configured.

• Start a session in the Prometheus host virtual machine.

  ssh -i prometheus.pem ubuntu@ec2-3-17-28.53.us-east-2.compute.amazonaws.com
  

• Edit /etc/prometheus/prometheus.yml file.

global:
  scrape_interval: 15s
  external_labels:
    monitor: 'prometheus'

scrape_configs:

  - job_name: 'node_exporter'

    static_configs:

      - targets: ['ec2-13-58-127-241.us-east-2.compute.amazonaws.com:9100']

Remember that ec2-13-58-127-241.us-east-2.compute.amazonaws.com is the DNS value I got from my configuration and yours should be something different.

• Restart Prometheus service.

  sudo systemctl restart prometheus
  

Try It Out

Now in your browser navigate to http://ec2-3-17-28.53.us-east-2.compute.amazonaws.com:9090/targets . Remember to change the url accordingly to your Prometheus AWS EC2 instance details and you should see something similar to this:

More Information

For more information you can visit Prometheus Node Exporter guide or the Node Exporter Github repository.