hosts/monitoring-3: move to blackbox monitoring

modules/monitoring/default.nix

@@ -22,6 +22,7 @@ in
         description = "Public Key of the monitoring wireguard interface of this host";
       };
       bird = mkEnableOption "Monitor bird";
+      blackbox = mkEnableOption "Monitor blackbox";
     };
   };
 
@@ -54,5 +55,24 @@ in
       openFirewall = true;
       firewallFilter = "-i wg-monitoring -p tcp -m tcp --dport 9324";
     };
+
+    services.prometheus.exporters.blackbox = mkIf cfg.blackbox {
+      enable = true;
+      openFirewall = true;
+      firewallFilter = "-i wg-monitoring -p tcp -m tcp --dport 9115";
+      configFile = pkgs.writeText "blackbox.yml" ''
+        modules:
+          icmp6:
+            prober: icmp
+            icmp:
+              preferred_ip_protocol: ip6
+              ip_protocol_fallback: false
+          icmp4:
+            prober: icmp
+            icmp:
+              preferred_ip_protocol: ip4
+              ip_protocol_fallback: false
+      '';
+    };
   };
 }