correctly discover the Alertmanager cluster and ServiceMonitors

manifests/prometheus/prometheus-k8s-cm.yaml

@@ -1,6 +1,25 @@
 apiVersion: v1
 data:
   prometheus.yaml: |
+    alerting:
+      alertmanagers:
+      - kubernetes_sd_configs:
+        - role: endpoints
+        relabel_configs:
+        - action: keep
+          regex: alertmanager-main
+          source_labels:
+          - __meta_kubernetes_service_name
+        - action: keep
+          regex: monitoring
+          source_labels:
+          - __meta_kubernetes_namespace
+        - action: keep
+          regex: web
+          source_labels:
+          - __meta_kubernetes_endpoint_port_name
+        scheme: http
+
     global:
       scrape_interval: 15s
       evaluation_interval: 15s

manifests/prometheus/prometheus-k8s.yaml

@@ -13,8 +13,3 @@ spec:
       # production use. This value is mainly meant for demonstration/testing
       # purposes.
       memory: 400Mi
-  alerting:
-    alertmanagers:
-    - namespace: monitoring
-      name: alertmanager-main
-      port: web