diff --git a/cmd/watchdog/main.go b/cmd/watchdog/main.go
index 8f3db2e..9799e61 100755
--- a/cmd/watchdog/main.go
+++ b/cmd/watchdog/main.go
@@ -7,11 +7,18 @@ import (
 	"time"
 
 	"github.com/go-ping/ping"
-	_ "github.com/go-ping/ping"
 
 	"github.com/tursom/esxi-monitor/vmomi"
 )
 
+type (
+	watchdog struct {
+		addr string
+		vm   *vmomi.VirtualMachine
+		life int
+	}
+)
+
 func main() {
 	cfg, err := parseConfig("config.yaml")
 	if err != nil {
@@ -34,7 +41,7 @@ func main() {
 	}
 
 	// ip -> vm instance
-	watches := make(map[string]*vmomi.VirtualMachine)
+	watches := make([]*watchdog, 0)
 	for _, vm := range vms {
 		target, contains := watchTargets[vm.Name()]
 		if !contains {
@@ -42,51 +49,76 @@ func main() {
 		}
 
 		fmt.Printf("watching virtual machine: addr=%s, name=%s\n", target.Addr, vm.Name())
-		watches[target.Addr] = vm
+		watches = append(watches, &watchdog{
+			addr: target.Addr,
+			vm:   vm,
+			life: 3,
+		})
 	}
 
 	doWatch(watches)
 }
 
 // watches map ip -> vm instance
-func doWatch(watches map[string]*vmomi.VirtualMachine) {
+func doWatch(watches []*watchdog) {
 	t := time.NewTicker(time.Minute)
 	for {
 		<-t.C
 
-		for ip, vm := range watches {
-			pinger, err := ping.NewPinger(ip)
+		fmt.Println("in ping tick")
+
+		for _, w := range watches {
+			pinger, err := ping.NewPinger(w.addr)
 			if err != nil {
 				_, _ = fmt.Fprintf(os.Stderr, "ping to target failed: %s\n", err)
 
 				continue
 			}
 
+			pinger.Timeout = time.Second * 15
 			pinger.Count = 4
 
+			fmt.Printf("start ping to %s\n", w.addr)
 			err = pinger.Run()
 			if err != nil {
 				_, _ = fmt.Fprintf(os.Stderr, "ping to target failed: %s\n", err)
 				continue
 			}
+			fmt.Printf("finished ping to %s\n", w.addr)
 
 			statistics := pinger.Statistics()
-			if statistics.PacketsRecv == 0 {
-				fmt.Printf("restarting vm %s(%s)", ip, vm.Name())
+			if statistics.PacketsRecv != 0 {
+				w.life = 3
+				continue
+			}
 
-				task, err := vm.Reset()
-				if err != nil {
-					_, _ = fmt.Fprintf(os.Stderr, "restart vm failed: %s\n", err)
-					continue
-				}
+			w.life--
+			fmt.Printf("ping vm %s(%s) failed, left %d life", w.addr, w.vm.Name(), w.life)
 
-				ctx, _ := context.WithTimeout(context.Background(), time.Minute)
-				err = task.Wait(ctx)
-				if err != nil {
-					_, _ = fmt.Fprintf(os.Stderr, "restart vm failed: %s\n", err)
-					continue
-				}
+			if w.life > 0 {
+				continue
+			}
+
+			fmt.Printf("restarting vm %s(%s)", w.addr, w.vm.Name())
+
+			if err := reset(w.vm); err != nil {
+				_, _ = fmt.Fprintf(os.Stderr, "restart vm failed: %s\n", err)
 			}
 		}
 	}
 }
+
+func reset(vm *vmomi.VirtualMachine) error {
+	task, err := vm.Reset()
+	if err != nil {
+		return err
+	}
+
+	ctx, _ := context.WithTimeout(context.Background(), time.Minute)
+	err = task.Wait(ctx)
+	if err != nil {
+		return err
+	}
+
+	return nil
+}
diff --git a/cmd/watchdog/watchdog b/cmd/watchdog/watchdog
new file mode 100755
index 0000000..2472358
Binary files /dev/null and b/cmd/watchdog/watchdog differ
diff --git a/watchdog b/watchdog
new file mode 120000
index 0000000..d50d139
--- /dev/null
+++ b/watchdog
@@ -0,0 +1 @@
+cmd/watchdog/watchdog
\ No newline at end of file