Add node-exporter for metrics collection

app/metrics/deploy/metrics.hcl

@@ -0,0 +1,25 @@
+job "metrics" {
+	datacenters = ["dc1"]
+	type = "system"
+	priority = "100"
+
+	group "node_exporter" {
+		task "node_exporter" {
+			driver = "docker"
+
+			config {
+				image = "quay.io/prometheus/node-exporter:latest"
+				network_mode = "host"
+				volumes = [
+					"/:/host:ro,rslave"
+				]
+				args = [ "--path.rootfs=/host" ]
+			}
+
+			resources {
+				cpu = 50
+				memory = 40
+			}
+		}
+	}
+}