--- lbbs/src/net_server.c	2025/12/25 05:20:09	1.113
+++ lbbs/src/net_server.c	2026/01/07 14:37:55	1.116
@@ -3,7 +3,7 @@
  * net_server
  *   - network server with SSH support
  *
- * Copyright (C) 2004-2025  Leaflet <leaflet@leafok.com>
+ * Copyright (C) 2004-2026  Leaflet <leaflet@leafok.com>
  */
 
 #ifdef HAVE_CONFIG_H
@@ -56,6 +56,7 @@
 
 enum _net_server_constant_t
 {
+	SOCKET_LISTEN_BACKLOG = 20,
 	WAIT_CHILD_PROCESS_EXIT_TIMEOUT = 5, // second
 	WAIT_CHILD_PROCESS_KILL_TIMEOUT = 1, // second
 
@@ -124,6 +125,7 @@ static int auth_password(ssh_session ses
 
 	if (ret == 0)
 	{
+		log_common("User [%s] authenticated successfully", user);
 		return SSH_AUTH_SUCCESS;
 	}
 
@@ -132,6 +134,8 @@ static int auth_password(ssh_session ses
 		sdata->error = 1;
 	}
 
+	log_common("User [%s] authentication failed (%d/%d)", user,
+			  sdata->tries, BBS_login_retry_times);
 	return SSH_AUTH_DENIED;
 }
 
@@ -633,7 +637,7 @@ int net_server(const char *hostaddr, in_
 			return -1;
 		}
 
-		if (listen(socket_server[i], 10) < 0)
+		if (listen(socket_server[i], SOCKET_LISTEN_BACKLOG) < 0)
 		{
 			log_error("Telnet socket listen error (%d)", errno);
 			return -1;