diff --git a/vnt/src/channel/context.rs b/vnt/src/channel/context.rs
index 869a963..a221ced 100644
--- a/vnt/src/channel/context.rs
+++ b/vnt/src/channel/context.rs
@@ -28,6 +28,7 @@ impl Context {
         is_tcp: bool,
         packet_loss_rate: Option<f64>,
         packet_delay: u32,
+        use_ipv6: bool,
     ) -> Self {
         let channel_num = main_udp_socket.len();
         assert_ne!(channel_num, 0, "not channel");
@@ -51,6 +52,7 @@ impl Context {
             packet_loss_rate,
             packet_delay,
             main_index: AtomicUsize::new(0),
+            use_ipv6,
         };
         Self {
             inner: Arc::new(inner),
@@ -70,7 +72,7 @@ impl Deref for Context {
 }
 
 /// 对称网络增加的udp socket数目，有助于增加打洞成功率
-pub const SYMMETRIC_CHANNEL_NUM: usize = 64;
+pub const SYMMETRIC_CHANNEL_NUM: usize = 100;
 const PACKET_LOSS_RATE_DENOMINATOR: u32 = 100_0000;
 pub struct ContextInner {
     // 核心udp socket
@@ -90,6 +92,7 @@ pub struct ContextInner {
     //控制延迟
     packet_delay: u32,
     main_index: AtomicUsize,
+    use_ipv6: bool,
 }
 
 impl ContextInner {
@@ -172,15 +175,16 @@ impl ContextInner {
         }
     }
     pub fn send_main_udp(&self, index: usize, buf: &[u8], mut addr: SocketAddr) -> io::Result<()> {
-        //核心udp socket都是ipv6模式,如果是v4地址则需要转换成v6
-        //只有服务器地址可能需要这样转换
-        if let SocketAddr::V4(ipv4) = addr {
-            addr = SocketAddr::V6(SocketAddrV6::new(
-                ipv4.ip().to_ipv6_mapped(),
-                ipv4.port(),
-                0,
-                0,
-            ));
+        if self.use_ipv6 {
+            //如果是v4地址则需要转换成v6
+            if let SocketAddr::V4(ipv4) = addr {
+                addr = SocketAddr::V6(SocketAddrV6::new(
+                    ipv4.ip().to_ipv6_mapped(),
+                    ipv4.port(),
+                    0,
+                    0,
+                ));
+            }
         }
         self.main_udp_socket[index].send_to(buf, addr)?;
         Ok(())
@@ -208,17 +212,9 @@ impl ContextInner {
             thread::sleep(Duration::from_millis(1));
         }
     }
-    pub fn try_send_all_main(&self, buf: &[u8], mut addr: SocketAddr) {
-        if let SocketAddr::V4(ipv4) = addr {
-            addr = SocketAddr::V6(SocketAddrV6::new(
-                ipv4.ip().to_ipv6_mapped(),
-                ipv4.port(),
-                0,
-                0,
-            ));
-        }
-        for udp in &self.main_udp_socket {
-            if let Err(e) = udp.send_to(buf, addr) {
+    pub fn try_send_all_main(&self, buf: &[u8], addr: SocketAddr) {
+        for index in 0..self.channel_num() {
+            if let Err(e) = self.send_main_udp(index, buf, addr) {
                 log::warn!("{:?},add={:?}", e, addr);
             }
         }
diff --git a/vnt/src/channel/mod.rs b/vnt/src/channel/mod.rs
index 6b0dd28..ebc6cf8 100644
--- a/vnt/src/channel/mod.rs
+++ b/vnt/src/channel/mod.rs
@@ -154,13 +154,31 @@ pub fn init_context(
 ) -> io::Result<(Context, mio::net::TcpListener)> {
     assert!(!ports.is_empty(), "not channel");
     let mut udps = Vec::with_capacity(ports.len());
+    //检查系统是否支持ipv6
+    let use_ipv6 = match socket2::Socket::new(socket2::Domain::IPV6, socket2::Type::DGRAM, None) {
+        Ok(_) => true,
+        Err(e) => {
+            log::warn!("{:?}", e);
+            false
+        }
+    };
     for port in &ports {
         //监听v6+v4双栈
-        let address: SocketAddr = format!("[::]:{}", port).parse().unwrap();
-        let socket = socket2::Socket::new(socket2::Domain::IPV6, socket2::Type::DGRAM, None)?;
-        io_convert(socket.set_only_v6(false), |_| {
-            format!("set_only_v6 failed: {}", &address)
-        })?;
+        let (socket, address) = if use_ipv6 {
+            let address: SocketAddr = format!("[::]:{}", port).parse().unwrap();
+            let socket = socket2::Socket::new(socket2::Domain::IPV6, socket2::Type::DGRAM, None)?;
+            io_convert(socket.set_only_v6(false), |_| {
+                format!("set_only_v6 failed: {}", &address)
+            })?;
+            (socket, address)
+        } else {
+            let address: SocketAddr = format!("0.0.0.0:{}", port).parse().unwrap();
+            (
+                socket2::Socket::new(socket2::Domain::IPV4, socket2::Type::DGRAM, None)?,
+                address,
+            )
+        };
+
         io_convert(socket.set_reuse_address(true), |_| {
             format!("set_reuse_address failed: {}", &address)
         })?;
@@ -184,15 +202,24 @@ pub fn init_context(
         is_tcp,
         packet_loss_rate,
         packet_delay,
+        use_ipv6,
     );
 
     let port = context.main_local_udp_port()?[0];
     //监听v6+v4双栈，tcp通道使用异步io
-    let address: SocketAddr = format!("[::]:{}", port).parse().unwrap();
-    let socket = socket2::Socket::new(socket2::Domain::IPV6, socket2::Type::STREAM, None)?;
-    io_convert(socket.set_only_v6(false), |_| {
-        format!("set_only_v6 failed: {}", &address)
-    })?;
+    let (socket, address) = if use_ipv6 {
+        let address: SocketAddr = format!("[::]:{}", port).parse().unwrap();
+        let socket = socket2::Socket::new(socket2::Domain::IPV6, socket2::Type::STREAM, None)?;
+        io_convert(socket.set_only_v6(false), |_| {
+            format!("set_only_v6 failed: {}", &address)
+        })?;
+        (socket, address)
+    } else {
+        let address: SocketAddr = format!("0.0.0.0:{}", port).parse().unwrap();
+        let socket = socket2::Socket::new(socket2::Domain::IPV4, socket2::Type::STREAM, None)?;
+        (socket, address)
+    };
+
     io_convert(socket.set_reuse_address(true), |_| {
         format!("set_reuse_address failed: {}", &address)
     })?;
@@ -200,7 +227,11 @@ pub fn init_context(
         if ports[0] == 0 {
             //端口可能冲突，则使用任意端口
             log::warn!("监听tcp端口失败 {:?},重试一次", address);
-            let address: SocketAddr = format!("[::]:{}", 0).parse().unwrap();
+            let address: SocketAddr = if use_ipv6 {
+                format!("[::]:{}", 0).parse().unwrap()
+            } else {
+                format!("0.0.0.0:{}", port).parse().unwrap()
+            };
             io_convert(socket.bind(&address.into()), |_| {
                 format!("bind failed: {}", &address)
             })?;