diff --git a/Makefile b/Makefile
index c427fef..7f267a9 100644
--- a/Makefile
+++ b/Makefile
@@ -9,11 +9,11 @@ kill:
 	sudo pkill -9 sower || true
 
 client: build kill
-	sudo $(PWD)/sower -f conf/sower.toml
+	sudo $(PWD)/sower -f conf/sower.toml -logtostderr
 
 server: build kill
-	$(PWD)/sower -D true
+	$(PWD)/sower -logtostderr -v 1
 
 run: build kill
-	$(PWD)/sower -D true &
-	sudo $(PWD)/sower -f conf/sower.toml
+	$(PWD)/sower -logtostderr -v 1 &
+	sudo $(PWD)/sower -f conf/sower.toml -logtostderr
diff --git a/conf/conf.go b/conf/conf.go
index ba25054..d15119d 100644
--- a/conf/conf.go
+++ b/conf/conf.go
@@ -2,6 +2,7 @@ package conf
 
 import (
 	"flag"
+	"strconv"
 
 	"github.com/BurntSushi/toml"
 )
@@ -12,15 +13,14 @@ var Conf = struct {
 	ServerAddr string   `toml:"server_addr"`
 	DnsServer  string   `toml:"dns_server"`
 	BlockList  []string `toml:"blocklist"`
-	Debug      bool     `toml:"debug"`
+	Verbose    int      `toml:"verbose"`
 }{}
 
 func init() {
 	flag.StringVar(&Conf.ConfigFile, "f", "", "config file location")
 	flag.StringVar(&Conf.ServerPort, "P", "5533", "server mode listen port")
-	flag.StringVar(&Conf.ServerAddr, "s", "", "server addr (run in client mode if set)")
+	flag.StringVar(&Conf.ServerAddr, "s", "", "server IP (run in client mode if set)")
 	flag.StringVar(&Conf.DnsServer, "d", "114.114.114.114", "client dns server")
-	flag.BoolVar(&Conf.Debug, "D", false, "run in debug mode")
 
 	if !flag.Parsed() {
 		flag.Parse()
@@ -32,4 +32,9 @@ func init() {
 	if _, err := toml.DecodeFile(Conf.ConfigFile, &Conf); err != nil {
 		panic(err)
 	}
+
+	// for glog
+	if err := flag.Set("v", strconv.Itoa(Conf.Verbose)); err != nil {
+		panic(err)
+	}
 }
diff --git a/conf/sower.toml b/conf/sower.toml
index a64b788..063fbca 100644
--- a/conf/sower.toml
+++ b/conf/sower.toml
@@ -6,4 +6,4 @@ blocklist=[
     "*.youtube.com",
     "zh.wikipedia.org",
 ]
-debug=true
\ No newline at end of file
+verbose=1
\ No newline at end of file
diff --git a/dns/dns.go b/dns/dns.go
index 8abd38a..6da5ec2 100644
--- a/dns/dns.go
+++ b/dns/dns.go
@@ -1,13 +1,12 @@
 package dns
 
 import (
-	"log"
 	"net"
 	"strings"
 	"time"
 
+	"github.com/golang/glog"
 	"github.com/miekg/dns"
-	"github.com/wweir/sower/conf"
 )
 
 func StartDNS(dnsServer string, blocklist []string) {
@@ -35,7 +34,7 @@ func StartDNS(dnsServer string, blocklist []string) {
 
 	server := &dns.Server{Addr: ":53", Net: "udp"}
 	server.TsigSecret = map[string]string{"axfr.": "so6ZGir4GPAqINNh9U5c3A=="}
-	log.Fatalln(server.ListenAndServe())
+	glog.Fatalln(server.ListenAndServe())
 }
 
 // TODO: delete me
@@ -59,7 +58,7 @@ func bestTry(w dns.ResponseWriter, r *dns.Msg, name, dnsServer string) {
 	}
 
 	if _, err := net.DialTimeout("tcp", ip+":http", time.Second); err != nil {
-		log.Println(ip+":80", err)
+		glog.V(2).Infoln(ip+":80", err)
 		rr, _ := dns.NewRR(name + " A 127.0.0.1")
 		r.Answer = []dns.RR{rr}
 		w.WriteMsg(r)
@@ -76,26 +75,19 @@ func initRule(blocklist []string) {
 	for i := range blocklist {
 		rule.Add(strings.Split(blocklist[i], "."))
 	}
-
-	if conf.Conf.Debug {
-		log.Printf("block rule:\n%s", rule)
-	}
+	glog.V(1).Infof("block rule:\n%s", rule)
 }
 
 func manual(w dns.ResponseWriter, r *dns.Msg, name, dnsServer string) {
 	if rule.Match(strings.TrimSuffix(name, ".")) {
-		if conf.Conf.Debug {
-			log.Printf("match %s suss", name)
-		}
+		glog.V(2).Infof("match %s suss", name)
 
 		rr, _ := dns.NewRR(name + " A 127.0.0.1")
 		r.Answer = []dns.RR{rr}
 		w.WriteMsg(r)
 		return
 	}
-	if conf.Conf.Debug {
-		log.Printf("match %s fail", name)
-	}
+	glog.V(2).Infof("match %s fail", name)
 
 	msg, err := dns.Exchange(r, dnsServer+":53")
 	if err != nil || len(msg.Answer) == 0 {
diff --git a/go.mod b/go.mod
index 886cdee..fe0ee99 100644
--- a/go.mod
+++ b/go.mod
@@ -4,6 +4,7 @@ require (
 	github.com/BurntSushi/toml v0.3.1
 	github.com/bifurcation/mint v0.0.0-20181105071958-a14404e9a861 // indirect
 	github.com/cheekybits/genny v1.0.0 // indirect
+	github.com/golang/glog v0.0.0-20160126235308-23def4e6c14b
 	github.com/golang/mock v1.1.1 // indirect
 	github.com/hashicorp/golang-lru v0.5.0 // indirect
 	github.com/lucas-clemente/aes12 v0.0.0-20171027163421-cd47fb39b79f // indirect
diff --git a/go.sum b/go.sum
index 43bb322..3a7133f 100644
--- a/go.sum
+++ b/go.sum
@@ -6,6 +6,8 @@ github.com/cheekybits/genny v1.0.0 h1:uGGa4nei+j20rOSeDeP5Of12XVm7TGUd4dJA9RDitf
 github.com/cheekybits/genny v1.0.0/go.mod h1:+tQajlRqAUrPI7DOSpB0XAqZYtQakVtB7wXkRAgjxjQ=
 github.com/fsnotify/fsnotify v1.4.7 h1:IXs+QLmnXW2CcXuY+8Mzv/fWEsPGWxqefPtCP5CnV9I=
 github.com/fsnotify/fsnotify v1.4.7/go.mod h1:jwhsz4b93w/PPRr/qN1Yymfu8t87LnFCMoQvtojpjFo=
+github.com/golang/glog v0.0.0-20160126235308-23def4e6c14b h1:VKtxabqXZkF25pY9ekfRL6a582T4P37/31XEstQ5p58=
+github.com/golang/glog v0.0.0-20160126235308-23def4e6c14b/go.mod h1:SBH7ygxi8pfUlaOkMMuAQtPIUF8ecWP5IEl/CR7VP2Q=
 github.com/golang/mock v1.1.1 h1:G5FRp8JnTd7RQH5kemVNlMeyXQAztQ3mOWV95KxsXH8=
 github.com/golang/mock v1.1.1/go.mod h1:oTYuIxOrZwtPieC+H1uAHpcLFnEyAGVDL/k47Jfbm0A=
 github.com/golang/protobuf v1.2.0 h1:P3YflyNX/ehuJFLhxviNdFxQPkGK5cDcApsge1SqnvM=
diff --git a/main.go b/main.go
index 5f898f5..86fefde 100644
--- a/main.go
+++ b/main.go
@@ -1,23 +1,19 @@
 package main
 
 import (
-	"log"
-
+	"github.com/golang/glog"
 	"github.com/wweir/sower/conf"
 	"github.com/wweir/sower/dns"
 	"github.com/wweir/sower/proxy"
 )
 
-func init() {
-	log.SetFlags(log.LstdFlags | log.Lshortfile)
-}
 func main() {
-	log.Println(conf.Conf)
+	glog.Infoln("Starting:", conf.Conf)
 
 	if conf.Conf.ServerAddr == "" {
 		proxy.StartServer(conf.Conf.ServerPort)
 	} else {
-		dns.StartDNS(conf.Conf.DnsServer, conf.Conf.BlockList)
+		go dns.StartDNS(conf.Conf.DnsServer, conf.Conf.BlockList)
 		proxy.StartClient(conf.Conf.ServerAddr)
 	}
 }
diff --git a/proxy/client.go b/proxy/client.go
index 62876a4..1c31631 100644
--- a/proxy/client.go
+++ b/proxy/client.go
@@ -1,9 +1,9 @@
 package proxy
 
 import (
-	"log"
 	"net"
 
+	"github.com/golang/glog"
 	"github.com/lucas-clemente/quic-go"
 )
 
@@ -11,18 +11,18 @@ func StartClient(server string) {
 	connCh := listenLocal([]string{":80", ":443"})
 	sess, err := quic.DialAddr(server, nil, nil)
 	if err != nil {
-		log.Printf("connect to remote(%s) fail:%s\n", server, err)
-		return
+		glog.Fatalf("connect to remote(%s) fail:%s\n", server, err)
 	}
 
 	for {
 		go func(conn net.Conn) {
+			glog.V(1).Infoln("new request to", conn.RemoteAddr())
 			defer conn.Close()
 			conn.(*net.TCPConn).SetKeepAlive(true)
 
 			stream, err := sess.OpenStream()
 			if err != nil {
-				log.Printf("connect to remote(%s) fail:%s\n", server, err)
+				glog.Warningf("connect to remote(%s) fail:%s\n", server, err)
 				return
 			}
 			defer stream.Close()
@@ -38,13 +38,13 @@ func listenLocal(ports []string) <-chan net.Conn {
 		go func(port string) {
 			ln, err := net.Listen("tcp", port)
 			if err != nil {
-				log.Fatalln(err)
+				glog.Fatalln(err)
 			}
 
 			for {
 				conn, err := ln.Accept()
 				if err != nil {
-					log.Println("accept", port, "fail:", err)
+					glog.Errorln("accept", port, "fail:", err)
 				}
 
 				connCh <- conn
@@ -52,5 +52,6 @@ func listenLocal(ports []string) <-chan net.Conn {
 		}(ports[i])
 	}
 
+	glog.Infoln("listening ports:", ports)
 	return connCh
 }
diff --git a/proxy/server.go b/proxy/server.go
index cc040b9..340dddf 100644
--- a/proxy/server.go
+++ b/proxy/server.go
@@ -1,9 +1,9 @@
 package proxy
 
 import (
-	"log"
 	"net"
 
+	"github.com/golang/glog"
 	"github.com/lucas-clemente/quic-go"
 	"github.com/wweir/sower/parser"
 )
@@ -11,13 +11,13 @@ import (
 func StartServer(port string) {
 	ln, err := quic.ListenAddr(":"+port, nil, nil)
 	if err != nil {
-		log.Fatalln(err)
+		glog.Fatalln(err)
 	}
 
 	for {
 		sess, err := ln.Accept()
 		if err != nil {
-			log.Println(err)
+			glog.Errorln(err)
 		}
 		go acceptSession(sess)
 	}
@@ -27,7 +27,7 @@ func acceptSession(sess quic.Session) {
 	for {
 		stream, err := sess.AcceptStream()
 		if err != nil {
-			log.Println(err)
+			glog.Errorln(err)
 		}
 		go acceptStream(stream, sess)
 	}
@@ -38,14 +38,14 @@ func acceptStream(stream quic.Stream, sess quic.Session) {
 
 	conn, addr, err := parser.ParseAddr(&streamConn{stream, sess})
 	if err != nil {
-		log.Panicln(err)
+		glog.Warningln(err)
 		return
 	}
-	log.Println(addr)
+	glog.V(1).Infoln(addr)
 
 	rc, err := net.Dial("tcp", addr)
 	if err != nil {
-		log.Println(err)
+		glog.Warningln(err)
 		return
 	}
 	defer rc.Close()
diff --git a/proxy/util.go b/proxy/util.go
index 53b42f3..7d58220 100644
--- a/proxy/util.go
+++ b/proxy/util.go
@@ -2,12 +2,12 @@ package proxy
 
 import (
 	"io"
-	"log"
 	"net"
 	"sync"
 	"sync/atomic"
 	"time"
 
+	"github.com/golang/glog"
 	"github.com/lucas-clemente/quic-go"
 )
 
@@ -35,7 +35,7 @@ func relay(conn1, conn2 net.Conn) {
 
 func redirect(conn1, conn2 net.Conn, wg *sync.WaitGroup, exitFlag *int32) {
 	if _, err := io.Copy(conn2, conn1); err != nil && (atomic.LoadInt32(exitFlag) == 0) {
-		log.Printf("%s<>%s -> %s<>%s: %s", conn1.RemoteAddr(), conn1.LocalAddr(), conn2.LocalAddr(), conn2.RemoteAddr(), err)
+		glog.V(1).Infof("%s<>%s -> %s<>%s: %s", conn1.RemoteAddr(), conn1.LocalAddr(), conn2.LocalAddr(), conn2.RemoteAddr(), err)
 	}
 
 	// wakeup all conn goroutine