configure opentelemetry on orbi

nixos/machines/orbi/configuration.nix

@@ -40,9 +40,10 @@
     # ---------
     #./loki.nix
     #./loki-promtail.nix
-    ##./prometheus.nix
     #./grafana.nix
-    ./telegraf.nix
+    ./system-telegraf.nix
+    ./system-opentelemetry.nix
+    #./system-prometheus.nix
 
     #./cache.nix
   ];

nixos/machines/orbi/system-opentelemetry.nix

@@ -0,0 +1,51 @@
+{ pkgs, ... }:
+{
+  services.opentelemetry-collector = {
+    enable = true;
+    package = pkgs.unstable.opentelemetry-collector-contrib;
+    settings = {
+      receivers = {
+        # provide a influxdb sink
+        influxdb = {
+          endpoint = "127.0.0.1:8088";
+        };
+        # scrape opentelemetry-colectors metrics
+        prometheus.config.scrape_configs = [
+          {
+            job_name = "netdata";
+            scrape_interval = "10s";
+            metrics_path = "/api/v1/allmetrics";
+            params.format = [ "prometheus" ];
+            static_configs = [{ targets = [ "127.0.0.1:19999" ]; }];
+          }
+          {
+            job_name = "otelcol";
+            scrape_interval = "10s";
+            static_configs = [{ targets = [ "127.0.0.1:8100" ]; }];
+            metric_relabel_configs = [
+              {
+                source_labels = [ "__name__" ];
+                regex = ".*grpc_io.*";
+                action = "drop";
+              }
+            ];
+          }
+        ];
+      };
+      exporters = {
+        # provide prometheus sink under `/metrics` to 
+        prometheus = {
+          endpoint = "127.0.0.1:8090";
+        };
+      };
+      service = {
+        pipelines.metrics = {
+          receivers = [ "influxdb" "prometheus" ];
+          exporters = [ "prometheus" ];
+        };
+        # open telemetries own metrics?
+        telemetry.metrics.address = "0.0.0.0:8100";
+      };
+    };
+  };
+}

nixos/machines/orbi/system-telegraf.nix

@@ -2,9 +2,14 @@
   services.telegraf = {
     enable = true;
     extraConfig = {
-      outputs.prometheus_client = {
-        listen = ":9273";
-        metric_version = 2;
+      outputs = {
+        prometheus_client = {
+          listen = ":9273";
+          metric_version = 2;
+        };
+        influxdb_v2 = {
+          urls = [ "http://127.0.0.1:8088" ];
+        };
       };
       # https://github.com/influxdata/telegraf/tree/master/plugins/inputs < all them plugins
       inputs = {