Monitoring with Prometheus

Author: Fabrice JAMMES (LinkedIn).

Prerequisites

# Launch the toolbox
ktbx desk

# Check your use kind-kind context
kubectx

#Launch initialization script
/home/k8s0/openshift-advanced/labs/3_policies/ex4-network.sh

# go to correct namespace
kubens network-k8s<ID>

Kubernetes Monitoring Lab with Helm

Objective

The goal of this lab is to deploy the Prometheus Stack using Helm while following best practices in shell scripting.

Prerequisites

Ensure you have the following installed:

  • Kubernetes cluster (e.g., Minikube, Kind, or a cloud-managed cluster)
  • kubectl configured to access the cluster
  • helm installed
  • bash shell

Steps to Deploy Prometheus Stack

Note

The Prometheus installation is completed before the lab; the following instructions are for reference only.

Install Prometheus Stack

git clone https://github.com/k8s-school/demo-prometheus
cd demo-prometheus
./install.sh

6. Access Prometheus and Grafana

Once the deployment is complete, follow these exercises to interact with the monitoring stack:

  1. Watch all pods in the monitoring namespace:
Answer 
kubectl get pods -n monitoring --watch
  1. Retrieve Grafana password:
Answer 
# Add helm repository
helm repo add prometheus-community https://prometheus-community.github.io/helm-charts || echo "Unable to add repo prometheus-community"
helm repo add stable https://charts.helm.sh/stable --force-update
helm repo update

# Query helm configuration
helm show values prometheus-community/kube-prometheus-stack | grep adminPassword
  1. Port forward Prometheus web UI to access it in a web browser:
Answer 
kubectl port-forward -n monitoring prometheus-prometheus-stack-kube-prom-prometheus-0 9090

Eventually create a ssh tunnel if Kubernetes is secured behing a ssh bastion.

Then open your browser and go to: http://localhost:9090

Check the metrics and the alert rules.

  1. Port forward Grafana to access it in a web browser:

Retrieve the Grafana port using kubectl get svc ....

Answer 
# port-forward to svc
kubectl port-forward svc/prometheus-stack-grafana -n monitoring 8080:80

# or port-forward to pod
kubectl port-forward $(kubectl get  pods --selector=app.kubernetes.io/name=grafana -n  monitoring --output=jsonpath="{.items..metadata.name}") -n monitoring  3000

Eventually create a ssh tunnel if Kubernetes is secured behing a ssh bastion.

Then open your browser and go to: http://localhost:8080

Check the Kubernetes dashboards.

Conclusion

This lab guides you through deploying a monitoring stack using Helm and Kubernetes, allowing you to explore Prometheus and Grafana for cluster monitoring.

The prometheus demo is available here: https://github.com/k8s-school/demo-prometheus