From a814d7f8da1c4971e3cd6226848520055b2f396e Mon Sep 17 00:00:00 2001
From: Tobias Schmidt <ts@soundcloud.com>
Date: Wed, 15 Apr 2015 23:38:53 -0400
Subject: [PATCH 1/2] Document how to enable logging

Not everyone might have experience with glog's default settings, this
change intends to make the start for new users easier.
---
 README.md | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/README.md b/README.md
index 6cd449dd..38affb73 100644
--- a/README.md
+++ b/README.md
@@ -10,6 +10,12 @@ collectors.
     make
     ./node_exporter <flags>
 
+The node_exporter uses the [glog][glog] library for logging. With the default
+parameters, nothing will be logged. Use `-logtostderr` to enable logging to
+stderr and `--help` to see more options about logging.
+
+[glog]: https://godoc.org/github.com/golang/glog
+
 ## Running tests
 
     make test

From 626900fe21ba129548eec0304c1648533ac6a1a9 Mon Sep 17 00:00:00 2001
From: Tobias Schmidt <ts@soundcloud.com>
Date: Wed, 15 Apr 2015 23:51:09 -0400
Subject: [PATCH 2/2] Log version at startup

---
 Makefile         | 1 +
 node_exporter.go | 6 ++++++
 2 files changed, 7 insertions(+)

diff --git a/Makefile b/Makefile
index ad0d9c82..55d45aac 100644
--- a/Makefile
+++ b/Makefile
@@ -13,5 +13,6 @@
 
 VERSION  := 0.8.0
 TARGET   := node_exporter
+GOFLAGS  := -ldflags "-X main.Version $(VERSION)"
 
 include Makefile.COMMON
diff --git a/node_exporter.go b/node_exporter.go
index b0dcbc35..19ac81fe 100644
--- a/node_exporter.go
+++ b/node_exporter.go
@@ -22,6 +22,9 @@ import (
 const subsystem = "exporter"
 
 var (
+	// set at build time
+	Version = "0.0.0.dev"
+
 	configFile        = flag.String("config.file", "", "Path to config file.")
 	memProfile        = flag.String("debug.memprofile-file", "", "Write memory profile to this file upon receipt of SIGUSR1.")
 	listenAddress     = flag.String("web.listen-address", ":9100", "Address on which to expose metrics and web interface.")
@@ -137,6 +140,7 @@ func loadCollectors(file string) (map[string]collector.Collector, error) {
 
 func main() {
 	flag.Parse()
+
 	if *printCollectors {
 		fmt.Printf("Available collectors:\n")
 		for n, _ := range collector.Factories {
@@ -182,6 +186,8 @@ func main() {
 			</body>
 			</html>`))
 	})
+
+	glog.Infof("Starting node_exporter v%s at %s", Version, *listenAddress)
 	err = http.ListenAndServe(*listenAddress, nil)
 	if err != nil {
 		glog.Fatal(err)