diff --git a/core/server/main.go b/core/server/main.go
index 6649409..a8136c5 100644
--- a/core/server/main.go
+++ b/core/server/main.go
@@ -7,6 +7,7 @@ import (
 	"flag"
 	"fmt"
 	"log"
+	"net"
 	"os"
 	"runtime"
 	runtimeDebug "runtime/debug"
@@ -45,7 +46,17 @@ func RunCore() {
 	boxmain.DisableColor()
 
 	// RPC
-	fmt.Printf("Core listening at %v\n", "127.0.0.1:"+strconv.Itoa(*_port))
+	go func() {
+		for {
+			time.Sleep(100 * time.Millisecond)
+			conn, err := net.Dial("tcp", "127.0.0.1:"+strconv.Itoa(*_port))
+			if err == nil {
+				conn.Close()
+				fmt.Printf("Core listening at %v\n", "127.0.0.1:"+strconv.Itoa(*_port))
+				return
+			}
+		}
+	}()
 	err := gen.ListenAndServeLibcoreService("tcp", "127.0.0.1:"+strconv.Itoa(*_port), new(server))
 	if err != nil {
 		log.Fatalf("failed to listen: %v", err)
diff --git a/core/server/server.go b/core/server/server.go
index e2f2ab3..fa16392 100644
--- a/core/server/server.go
+++ b/core/server/server.go
@@ -49,7 +49,7 @@ func (s *server) Start(in *gen.LoadConfigReq, out *gen.ErrorResp) (_ error) {
 	}()
 
 	if debug {
-		log.Println("Start:", in.CoreConfig)
+		log.Println("Start:", *in.CoreConfig)
 	}
 
 	if boxInstance != nil {
@@ -420,15 +420,15 @@ func (s *server) QuerySpeedTest(in *gen.EmptyReq, out *gen.QuerySpeedTestRespons
 		errStr = res.Error.Error()
 	}
 	out.Result = &gen.SpeedTestResult{
-			DlSpeed:       To(res.DlSpeed),
-			UlSpeed:       To(res.UlSpeed),
-			Latency:       To(res.Latency),
-			OutboundTag:   To(res.Tag),
-			Error:         To(errStr),
-			ServerName:    To(res.ServerName),
-			ServerCountry: To(res.ServerCountry),
-			Cancelled:     To(res.Cancelled),
-		}
+		DlSpeed:       To(res.DlSpeed),
+		UlSpeed:       To(res.UlSpeed),
+		Latency:       To(res.Latency),
+		OutboundTag:   To(res.Tag),
+		Error:         To(errStr),
+		ServerName:    To(res.ServerName),
+		ServerCountry: To(res.ServerCountry),
+		Cancelled:     To(res.Cancelled),
+	}
 	out.IsRunning = To(isRunning)
 	return nil
 }