Hands-On Infrastructure Monitoring with Prometheus

Deployment

The test environment for static infrastructure for this chapter should already have node_exporter up and running through the automatic provisioning. Nevertheless, we can inspect it by connecting, for example, to the target01 VM as follows:

cd ./chapter06/vagrant ssh target01

Then check the configuration of the provided systemd unit file like so:

vagrant@target01:~$ systemctl cat node-exporter

In this snippet, we can see the textfile collector directory being set so that custom metrics can be exported:

...ExecStart=/usr/bin/node_exporter --collector.textfile.directory=/var/lib/node_exporter...

Let's try creating a custom metric. To do that, we only need to write the metric to a file inside the textfile collector directory with a ...