How to Set Up Prometheus for Ingress NGINX Manually

Getting Prometheus to monitor your Ingress NGINX without using Helm is totally doable, and it’s a great way to learn how everything connects. Here’s a step-by-step guide to get you started!

Step 1: Install Prometheus

You can deploy Prometheus using Kubernetes manifests. Here’s a basic example to help you get going:

apiVersion: v1
kind: Service
metadata:
  name: prometheus
  labels:
    app: prometheus
spec:
  ports:
    - port: 9090
      targetPort: 9090
  selector:
    app: prometheus
---
apiVersion: apps/v1
kind: Deployment
metadata:
  name: prometheus
spec:
  replicas: 1
  selector:
    matchLabels:
      app: prometheus
  template:
    metadata:
      labels:
        app: prometheus
    spec:
      containers:
        - name: prometheus
          image: prom/prometheus
          args:
            - "--config.file=/etc/prometheus/prometheus.yml"
            - "--storage.tsdb.path=/prometheus"
          ports:
            - containerPort: 9090
          volumeMounts:
            - name: prometheus-config
              mountPath: /etc/prometheus
            - name: prometheus-data
              mountPath: /prometheus
      volumes:
        - name: prometheus-config
          configMap:
            name: prometheus-config
        - name: prometheus-data
          emptyDir: {}
    

Step 2: Configure Prometheus

Here’s a simple prometheus.yml config that you might use:

global:
  scrape_interval: 15s
scrape_configs:
  - job_name: 'ingress-nginx'
    static_configs:
      - targets: [':10254']
    

Step 3: Enable Metrics on Ingress NGINX

To expose metrics from your Ingress NGINX controller, you’ll need to ensure metrics are enabled in the NGINX ConfigMap. Here’s how you can do that:

apiVersion: v1
kind: ConfigMap
metadata:
  name: nginx-configuration
  namespace: 
data:
  enable-vts-status: "true"
    

Step 4: Expose NGINX Metrics Endpoint

Check if your Ingress NGINX controller is exposing metrics on port 10254. You can access this endpoint at:

http://:10254/metrics

Step 5: Access Prometheus

After deploying everything, you should be able to access your Prometheus UI by port-forwarding:

kubectl port-forward svc/prometheus 9090:9090
    

Step 6: Verify Everything is Working

In Prometheus, go to the “Targets” page (usually available at http://localhost:9090/targets) and check if your Ingress NGINX is listed there. If all is well, you’re set!

Tips:

• ServiceMonitor: If you’re using the Prometheus Operator later, look into ServiceMonitors. For now, static configs will work.
• Keep It Clean: Make sure to label your resources properly so it’s easier to manage later.
• Explore: Familiarize yourself with Prometheus query language (PromQL) to make the most out of your metrics.

Hope this helps get you started with monitoring! Good luck diving deeper into Kubernetes and Prometheus!