Sysdig Tutorial: node-exporter-daemonset not working out of the box

[obitech]

Hey Mateo, I've just been following your (excellent) Kubernetes Monitoring with Prometheus tutorial and encountered an issue towards the end, where you deploy the node-exporter DaemonSet:

Here you mention to create a new namespace and pull a DaemonSet from another repo:

kubectl create ns monitoring 
kubectl create -f https://raw.githubusercontent.com/bakins/minikube-prometheus-demo/master/node-exporter-daemonset.yml

Unfortunately the repo is archived and seems to have some issues. In this case, the node-exporter pod created by the DaemonSet is not discoverable by Prometheus because of the seperate monitoring namespace (all previous resources have been launched in default).

For it to work, I had to create a headless Service for the pod:

kind: Service
apiVersion: v1
metadata:
  name: node-exporter
  namespace: monitoring
spec:
  selector:
    name: node-exporter
  ports:
  - port: 9100
    targetPort: 9100
  clusterIP: None
---

apiVersion: apps/v1
kind: DaemonSet
metadata:
  name: node-exporter
  namespace: monitoring
  labels:
    name: node-exporter
spec:
  selector:
    matchLabels:
      name: node-exporter
  template:
    metadata:
      labels:
        name: node-exporter
      annotations:
         prometheus.io/scrape: "true"
         prometheus.io/port: "9100"
    spec:
      hostPID: true
      hostIPC: true
      hostNetwork: true
      containers:
        - ports:
            - containerPort: 9100
              protocol: TCP
          resources:
            requests:
              cpu: 0.15
          securityContext:
            privileged: true
          image: prom/node-exporter:v0.15.2
          args:
            - --path.procfs
            - /host/proc
            - --path.sysfs
            - /host/sys
            - --collector.filesystem.ignored-mount-points
            - '"^/(sys|proc|dev|host|etc)($|/)"'
          name: node-exporter
          volumeMounts:
            - name: dev
              mountPath: /host/dev
            - name: proc
              mountPath: /host/proc
            - name: sys
              mountPath: /host/sys
            - name: rootfs
              mountPath: /rootfs
      volumes:
        - name: proc
          hostPath:
            path: /proc
        - name: dev
          hostPath:
            path: /dev
        - name: sys
          hostPath:
            path: /sys
        - name: rootfs
          hostPath:
            path: /

which makes it discoverable via DNS in the prometheus.yml:

# ...
  - job_name: 'node-exporter'
    static_configs:
    - targets: ['node-exporter.monitoring.svc.cluster.local:9100']

You might want to consider including it in the tutorial :)