Monitor prometheus metrics

services/monitoring/prometheus.nix

@@ -36,6 +36,9 @@
         ];
       }
     ];
+    globalConfig = {
+      scrape_interval = "15s";
+    };
     rules = [
       ''
         groups:
@@ -124,6 +127,14 @@
           }
         ];
       }
+      {
+        job_name = "prometheus";
+        static_configs = [
+          {
+            targets = [ "localhost:9090" ];
+          }
+        ];
+      }
       {
         job_name = "pve-exporter";
         static_configs = [