defiant: add uptime-kuma, rename metrics->monitoring

hosts/defiant/services/monitoring/prometheus.nix

@@ -0,0 +1,64 @@
+{ config, pkgs, ... }:
+
+let
+  cfg = config.services.prometheus;
+in {
+  services.prometheus = {
+    enable = true;
+    listenAddress = "127.0.0.1";
+    port = 9001;
+
+    # StateDirectory must be under /var/lib.
+    # TODO: Back up to /tank/services/metrics/prometheus
+
+    scrapeConfigs = [
+      {
+        job_name = "node";
+        static_configs = [
+          {
+            targets = [
+              "voyager.home.feal.no:9100"
+              "sulu.home.feal.no:9100"
+              "mccoy.home.feal.no:9100"
+              "dlink-feal.home.feal.no:9100"
+              "edison.home.feal.no:9100"
+              "defiant.home.feal.no:9100"
+              "scotty.home.feal.no:9100"
+            ];
+          }
+        ];
+      }
+      {
+        job_name = "openwrt";
+        static_configs = [
+          { targets = ["dlink-feal.home.feal.no:9100"]; }
+        ];
+      }
+      {
+        job_name = "snmp";
+        static_configs = [{
+          targets = [
+            "feal-syn1.home.feal.no"
+            "feal-syn2.home.feal.no"
+          ];
+        }];
+        metrics_path = "/snmp";
+        params.module = ["synology"];
+        relabel_configs = [
+          {
+            source_labels = ["__address__"];
+            target_label = "__param_target";
+          }
+          {
+            source_labels = ["__param_target"];
+            target_label = "instance";
+          }
+          {
+            target_label = "__address__";
+            replacement = "127.0.0.1:9116";
+          }
+        ];
+      }
+    ];
+  };
+}