After installing Prometheus, by connecting to its dashboard, you will notice a list of services already under monitoring: these are useful resources for the functioning of Prometheus itself (e.g. alertmanager, Grafana) or typical of each K8s cluster (apiserver, controller-manager, scheduler). But how do you monitor an application in general? As As an example, let's try to monitor Longhorn, a distributed block storage system for Kubernetes.
...