diff --git a/connector/relay/conn.go b/connector/relay/conn.go
index 4e9cc4f..e2d16a2 100644
--- a/connector/relay/conn.go
+++ b/connector/relay/conn.go
@@ -13,6 +13,7 @@ import (
 	"github.com/go-gost/core/common/bufpool"
 	mdata "github.com/go-gost/core/metadata"
 	"github.com/go-gost/relay"
+	xrelay "github.com/go-gost/x/internal/util/relay"
 )
 
 type tcpConn struct {
@@ -129,7 +130,7 @@ func readResponse(r io.Reader) (err error) {
 	}
 
 	if resp.Status != relay.StatusOK {
-		err = fmt.Errorf("status %d", resp.Status)
+		err = fmt.Errorf("%d %s", resp.Status, xrelay.StatusText(resp.Status))
 		return
 	}
 	return nil
@@ -223,16 +224,3 @@ func (c *bindUDPConn) RemoteAddr() net.Addr {
 func (c *bindUDPConn) Metadata() mdata.Metadata {
 	return c.md
 }
-
-type bindAddr struct {
-	network string
-	addr    string
-}
-
-func (p *bindAddr) Network() string {
-	return p.network
-}
-
-func (p *bindAddr) String() string {
-	return p.addr
-}
diff --git a/connector/tunnel/conn.go b/connector/tunnel/conn.go
index cd712b2..2a025bc 100644
--- a/connector/tunnel/conn.go
+++ b/connector/tunnel/conn.go
@@ -1,67 +1,24 @@
 package tunnel
 
 import (
-	"bytes"
 	"encoding/binary"
 	"errors"
 	"fmt"
 	"io"
 	"math"
 	"net"
-	"sync"
 
 	"github.com/go-gost/core/common/bufpool"
 	mdata "github.com/go-gost/core/metadata"
 	"github.com/go-gost/relay"
+	xrelay "github.com/go-gost/x/internal/util/relay"
 )
 
-type tcpConn struct {
-	net.Conn
-	wbuf *bytes.Buffer
-	once sync.Once
-}
-
-func (c *tcpConn) Read(b []byte) (n int, err error) {
-	c.once.Do(func() {
-		if c.wbuf != nil {
-			err = readResponse(c.Conn)
-		}
-	})
-
-	if err != nil {
-		return
-	}
-	return c.Conn.Read(b)
-}
-
-func (c *tcpConn) Write(b []byte) (n int, err error) {
-	n = len(b) // force byte length consistent
-	if c.wbuf != nil && c.wbuf.Len() > 0 {
-		c.wbuf.Write(b) // append the data to the cached header
-		_, err = c.Conn.Write(c.wbuf.Bytes())
-		c.wbuf.Reset()
-		return
-	}
-	_, err = c.Conn.Write(b)
-	return
-}
-
 type udpConn struct {
 	net.Conn
-	wbuf *bytes.Buffer
-	once sync.Once
 }
 
 func (c *udpConn) Read(b []byte) (n int, err error) {
-	c.once.Do(func() {
-		if c.wbuf != nil {
-			err = readResponse(c.Conn)
-		}
-	})
-	if err != nil {
-		return
-	}
-
 	var bb [2]byte
 	_, err = io.ReadFull(c.Conn, bb[:])
 	if err != nil {
@@ -88,14 +45,6 @@ func (c *udpConn) Write(b []byte) (n int, err error) {
 	}
 
 	n = len(b)
-	if c.wbuf != nil && c.wbuf.Len() > 0 {
-		var bb [2]byte
-		binary.BigEndian.PutUint16(bb[:], uint16(len(b)))
-		c.wbuf.Write(bb[:])
-		c.wbuf.Write(b) // append the data to the cached header
-		_, err = c.wbuf.WriteTo(c.Conn)
-		return
-	}
 
 	var bb [2]byte
 	binary.BigEndian.PutUint16(bb[:], uint16(len(b)))
@@ -119,7 +68,7 @@ func readResponse(r io.Reader) (err error) {
 	}
 
 	if resp.Status != relay.StatusOK {
-		err = fmt.Errorf("status %d", resp.Status)
+		err = fmt.Errorf("%d %s", resp.Status, xrelay.StatusText(resp.Status))
 		return
 	}
 	return nil
diff --git a/connector/tunnel/connector.go b/connector/tunnel/connector.go
index 824cf28..a427dfd 100644
--- a/connector/tunnel/connector.go
+++ b/connector/tunnel/connector.go
@@ -1,7 +1,6 @@
 package tunnel
 
 import (
-	"bytes"
 	"context"
 	"fmt"
 	"net"
@@ -90,39 +89,20 @@ func (c *tunnelConnector) Connect(ctx context.Context, conn net.Conn, network, a
 		ID: c.md.tunnelID.ID(),
 	})
 
-	if c.md.noDelay {
-		if _, err := req.WriteTo(conn); err != nil {
-			return nil, err
-		}
-		// drain the response
-		if err := readResponse(conn); err != nil {
-			return nil, err
-		}
+	if _, err := req.WriteTo(conn); err != nil {
+		return nil, err
+	}
+	// drain the response
+	if err := readResponse(conn); err != nil {
+		return nil, err
 	}
 
 	switch network {
 	case "tcp", "tcp4", "tcp6":
-		if !c.md.noDelay {
-			cc := &tcpConn{
-				Conn: conn,
-				wbuf: &bytes.Buffer{},
-			}
-			if _, err := req.WriteTo(cc.wbuf); err != nil {
-				return nil, err
-			}
-			conn = cc
-		}
 	case "udp", "udp4", "udp6":
-		cc := &udpConn{
+		conn = &udpConn{
 			Conn: conn,
 		}
-		if !c.md.noDelay {
-			cc.wbuf = &bytes.Buffer{}
-			if _, err := req.WriteTo(cc.wbuf); err != nil {
-				return nil, err
-			}
-		}
-		conn = cc
 	default:
 		err := fmt.Errorf("network %s is unsupported", network)
 		log.Error(err)
diff --git a/connector/tunnel/metadata.go b/connector/tunnel/metadata.go
index 4839cbe..d678b62 100644
--- a/connector/tunnel/metadata.go
+++ b/connector/tunnel/metadata.go
@@ -18,13 +18,11 @@ var (
 type metadata struct {
 	connectTimeout time.Duration
 	tunnelID       relay.TunnelID
-	noDelay        bool
 	muxCfg         *mux.Config
 }
 
 func (c *tunnelConnector) parseMetadata(md mdata.Metadata) (err error) {
 	c.md.connectTimeout = mdutil.GetDuration(md, "connectTimeout")
-	c.md.noDelay = mdutil.GetBool(md, "nodelay")
 
 	if s := mdutil.GetString(md, "tunnelID", "tunnel.id"); s != "" {
 		uuid, err := uuid.Parse(s)
diff --git a/internal/util/relay/conn.go b/internal/util/relay/conn.go
index 2d25125..865094d 100644
--- a/internal/util/relay/conn.go
+++ b/internal/util/relay/conn.go
@@ -6,8 +6,32 @@ import (
 
 	"github.com/go-gost/core/common/bufpool"
 	"github.com/go-gost/gosocks5"
+	"github.com/go-gost/relay"
 )
 
+func StatusText(code uint8) string {
+	switch code {
+	case relay.StatusBadRequest:
+		return "Bad Request"
+	case relay.StatusForbidden:
+		return "Forbidden"
+	case relay.StatusHostUnreachable:
+		return "Host Unreachable"
+	case relay.StatusInternalServerError:
+		return "Internal Server Error"
+	case relay.StatusNetworkUnreachable:
+		return "Network Unreachable"
+	case relay.StatusServiceUnavailable:
+		return "Service Unavailable"
+	case relay.StatusTimeout:
+		return "Timeout"
+	case relay.StatusUnauthorized:
+		return "Unauthorized"
+	default:
+		return ""
+	}
+}
+
 type udpTunConn struct {
 	net.Conn
 	taddr net.Addr