Print server addr if connect failed

.gitignore

@@ -1,6 +1,7 @@
 /target
 /build/*.tar.gz
 /build/*.tar.xz
+/build/*.zip
 /build/target
 /build/install
 /dev

src/relay/tcprelay/socks5_local.rs

@@ -8,7 +8,8 @@ use tokio::{
     self,
     net::{
         tcp::{ReadHalf, WriteHalf},
-        TcpListener, TcpStream,
+        TcpListener,
+        TcpStream,
     },
     prelude::*,
 };
@@ -55,7 +56,7 @@ async fn handle_socks5_connect<'a>(
             use crate::relay::socks5::Reply;
             use std::io::ErrorKind;
 
-            error!("Failed to connect remote server, err: {}", err);
+            error!("Failed to connect remote server {}, err: {}", svr_cfg.addr(), err);
 
             let reply = match err.kind() {
                 ErrorKind::ConnectionRefused => Reply::ConnectionRefused,

src/relay/tcprelay/tunnel_local.rs

@@ -32,6 +32,7 @@ async fn establish_client_tcp_tunnel<'a>(
         }
         Err(err) => {
             // Just close the connection.
+            error!("Failed to connect remote server {}, err: {}", svr_cfg.addr(), err);
             return Err(err);
         }
     };