diff --git a/include/mysql_connection.h b/include/mysql_connection.h
index 4f7573cd3..a0bb1f5e3 100644
--- a/include/mysql_connection.h
+++ b/include/mysql_connection.h
@@ -92,6 +92,8 @@ class MySQL_Connection {
 	bool processing_prepared_statement_execute;
 	bool processing_multi_statement;
 	bool multiplex_delayed;
+	bool unknown_transaction_status;
+	void compute_unknown_transaction_status();
 	MySQL_Connection();
 	~MySQL_Connection();
 	bool set_autocommit(bool);
diff --git a/lib/MySQL_Session.cpp b/lib/MySQL_Session.cpp
index c5862fb95..14d8b3467 100644
--- a/lib/MySQL_Session.cpp
+++ b/lib/MySQL_Session.cpp
@@ -942,6 +942,7 @@ int MySQL_Session::handler_again___status_PINGING_SERVER() {
 	int rc=myconn->async_ping(myds->revents);
 	if (rc==0) {
 		myconn->async_state_machine=ASYNC_IDLE;
+		myconn->unknown_transaction_status = false;
 		if (mysql_thread___multiplexing && (myconn->reusable==true) && myds->myconn->IsActiveTransaction()==false && myds->myconn->MultiplexDisabled()==false) {
 			myds->return_MySQL_Connection_To_Pool();
 		} else {
@@ -2730,6 +2731,7 @@ handler_again:
 								enum session_status st=status;
 								size_t sts=previous_status.size();
 								if (sts) {
+									myconn->unknown_transaction_status = false;
 									myconn->async_state_machine=ASYNC_IDLE;
 									myds->DSS=STATE_MARIADB_GENERIC;
 									st=previous_status.top();
@@ -2769,6 +2771,7 @@ handler_again:
 					if (mysql_thread___multiplexing && (myds->myconn->reusable==true) && myds->myconn->IsActiveTransaction()==false && myds->myconn->MultiplexDisabled()==false) {
 						if (mysql_thread___connection_delay_multiplex_ms && mirror==false) {
 							myds->wait_until=thread->curtime+mysql_thread___connection_delay_multiplex_ms*1000;
+							myconn->unknown_transaction_status = false;
 							myconn->async_state_machine=ASYNC_IDLE;
 							myconn->multiplex_delayed=true;
 							myds->DSS=STATE_MARIADB_GENERIC;
@@ -2796,6 +2799,7 @@ handler_again:
 						}
 					} else {
 						myconn->multiplex_delayed=false;
+						myconn->unknown_transaction_status = false;
 						myconn->async_state_machine=ASYNC_IDLE;
 						myds->DSS=STATE_MARIADB_GENERIC;
 						if (transaction_persistent==true) {
@@ -2813,6 +2817,7 @@ handler_again:
 				} else {
 					if (rc==-1) {
 						int myerr=mysql_errno(myconn->mysql);
+						myconn->compute_unknown_transaction_status();
 						char *errmsg = NULL;
 						if (myerr == 0) {
 							if (CurrentQuery.mysql_stmt) {
diff --git a/lib/mysql_connection.cpp b/lib/mysql_connection.cpp
index e566f10aa..d88b517cc 100644
--- a/lib/mysql_connection.cpp
+++ b/lib/mysql_connection.cpp
@@ -49,6 +49,29 @@ MySQL_Connection_userinfo::~MySQL_Connection_userinfo() {
 	if (schemaname) free(schemaname);
 }
 
+void MySQL_Connection::compute_unknown_transaction_status() {
+	if (mysql) {
+		int _myerrno=mysql_errno(mysql);
+		if (_myerrno == 0) {
+			unknown_transaction_status = false; // no error
+			return;
+		}
+		if (_myerrno >= 2000 && _myerrno < 3000) { // client error
+			// do not change it
+			return;
+		}
+		if (_myerrno >= 1000 && _myerrno < 2000) { // server error
+			unknown_transaction_status = true;
+			return;
+		}
+		if (_myerrno >= 3000 && _myerrno < 4000) { // server error
+			unknown_transaction_status = true;
+			return;
+		}
+		// all other cases, server error
+	}
+}
+
 uint64_t MySQL_Connection_userinfo::compute_hash() {
 	int l=0;
 	if (username)
@@ -189,6 +212,7 @@ MySQL_Connection::MySQL_Connection() {
 	largest_query_length=0;
 	multiplex_delayed=false;
 	MyRS=NULL;
+	unknown_transaction_status = false;
 	creation_time=0;
 	processing_multi_statement=false;
 	proxy_debug(PROXY_DEBUG_MYSQL_CONNPOOL, 4, "Creating new MySQL_Connection %p\n", this);
@@ -981,6 +1005,14 @@ handler_again:
 			}
 			break;
 		case ASYNC_QUERY_END:
+			if (mysql) {
+				int _myerrno=mysql_errno(mysql);
+				if (_myerrno == 0) {
+					unknown_transaction_status = false;
+				} else {
+					compute_unknown_transaction_status();
+				}
+			}
 			if (mysql_result) {
 				mysql_free_result(mysql_result);
 				mysql_result=NULL;
@@ -1137,6 +1169,7 @@ int MySQL_Connection::async_connect(short event) {
 		return 0;
 	}
 	if (async_state_machine==ASYNC_CONNECT_SUCCESSFUL) {
+		unknown_transaction_status = false;
 		async_state_machine=ASYNC_IDLE;
 		myds->wait_until=0;
 		creation_time = monotonic_time();
@@ -1145,6 +1178,7 @@ int MySQL_Connection::async_connect(short event) {
 	handler(event);
 	switch (async_state_machine) {
 		case ASYNC_CONNECT_SUCCESSFUL:
+			unknown_transaction_status = false;
 			async_state_machine=ASYNC_IDLE;
 			myds->wait_until=0;
 			return 0;
@@ -1224,8 +1258,10 @@ int MySQL_Connection::async_query(short event, char *stmt, unsigned long length,
 	
 	if (async_state_machine==ASYNC_QUERY_END) {
 		if (mysql_errno(mysql)) {
+			compute_unknown_transaction_status();
 			return -1;
 		} else {
+			unknown_transaction_status = false;
 			return 0;
 		}
 	}
@@ -1233,17 +1269,21 @@ int MySQL_Connection::async_query(short event, char *stmt, unsigned long length,
 		query.stmt_meta=NULL;
 		async_state_machine=ASYNC_QUERY_END;
 		if (mysql_stmt_errno(query.stmt)) {
+			compute_unknown_transaction_status();
 			return -1;
 		} else {
+			unknown_transaction_status = false;
 			return 0;
 		}
 	}
 	if (async_state_machine==ASYNC_STMT_PREPARE_SUCCESSFUL || async_state_machine==ASYNC_STMT_PREPARE_FAILED) {
 		query.stmt_meta=NULL;
 		if (async_state_machine==ASYNC_STMT_PREPARE_FAILED) {
+			compute_unknown_transaction_status();
 			return -1;
 		} else {
 			*_stmt=query.stmt;
+			unknown_transaction_status = false;
 			return 0;
 		}
 	}
@@ -1273,6 +1313,7 @@ int MySQL_Connection::async_ping(short event) {
 	assert(ret_mysql);
 	switch (async_state_machine) {
 		case ASYNC_PING_SUCCESSFUL:
+			unknown_transaction_status = false;
 			async_state_machine=ASYNC_IDLE;
 			return 0;
 			break;
@@ -1292,6 +1333,7 @@ int MySQL_Connection::async_ping(short event) {
 	// check again
 	switch (async_state_machine) {
 		case ASYNC_PING_SUCCESSFUL:
+			unknown_transaction_status = false;
 			async_state_machine=ASYNC_IDLE;
 			return 0;
 			break;
@@ -1314,6 +1356,7 @@ int MySQL_Connection::async_change_user(short event) {
 	assert(ret_mysql);
 	switch (async_state_machine) {
 		case ASYNC_CHANGE_USER_SUCCESSFUL:
+			unknown_transaction_status = false;
 			async_state_machine=ASYNC_IDLE;
 			return 0;
 			break;
@@ -1333,6 +1376,7 @@ int MySQL_Connection::async_change_user(short event) {
 	// check again
 	switch (async_state_machine) {
 		case ASYNC_CHANGE_USER_SUCCESSFUL:
+			unknown_transaction_status = false;
 			async_state_machine=ASYNC_IDLE;
 			return 0;
 			break;
@@ -1355,6 +1399,7 @@ int MySQL_Connection::async_select_db(short event) {
 	assert(ret_mysql);
 	switch (async_state_machine) {
 		case ASYNC_INITDB_SUCCESSFUL:
+			unknown_transaction_status = false;
 			async_state_machine=ASYNC_IDLE;
 			return 0;
 			break;
@@ -1371,6 +1416,7 @@ int MySQL_Connection::async_select_db(short event) {
 	// check again
 	switch (async_state_machine) {
 		case ASYNC_INITDB_SUCCESSFUL:
+			unknown_transaction_status = false;
 			async_state_machine=ASYNC_IDLE;
 			return 0;
 			break;
@@ -1390,6 +1436,7 @@ int MySQL_Connection::async_set_autocommit(short event, bool ac) {
 	assert(ret_mysql);
 	switch (async_state_machine) {
 		case ASYNC_SET_AUTOCOMMIT_SUCCESSFUL:
+			unknown_transaction_status = false;
 			async_state_machine=ASYNC_IDLE;
 			return 0;
 			break;
@@ -1407,6 +1454,7 @@ int MySQL_Connection::async_set_autocommit(short event, bool ac) {
 	// check again
 	switch (async_state_machine) {
 		case ASYNC_SET_AUTOCOMMIT_SUCCESSFUL:
+			unknown_transaction_status = false;
 			async_state_machine=ASYNC_IDLE;
 			return 0;
 			break;
@@ -1426,6 +1474,7 @@ int MySQL_Connection::async_set_names(short event, uint8_t c) {
 	assert(ret_mysql);
 	switch (async_state_machine) {
 		case ASYNC_SET_NAMES_SUCCESSFUL:
+			unknown_transaction_status = false;
 			async_state_machine=ASYNC_IDLE;
 			return 0;
 			break;
@@ -1443,6 +1492,7 @@ int MySQL_Connection::async_set_names(short event, uint8_t c) {
 	// check again
 	switch (async_state_machine) {
 		case ASYNC_SET_NAMES_SUCCESSFUL:
+			unknown_transaction_status = false;
 			async_state_machine=ASYNC_IDLE;
 			return 0;
 			break;
@@ -1487,6 +1537,7 @@ void MySQL_Connection::async_free_result() {
 			mysql_result=NULL;
 		}
 	}
+	unknown_transaction_status = false;
 	async_state_machine=ASYNC_IDLE;
 	if (MyRS) {
 		delete MyRS;
@@ -1499,7 +1550,7 @@ bool MySQL_Connection::IsActiveTransaction() {
 	bool ret=false;
 	if (mysql) {
 		ret = (mysql->server_status & SERVER_STATUS_IN_TRANS);
-		if (ret == false && (mysql)->net.last_errno) {
+		if (ret == false && (mysql)->net.last_errno && unknown_transaction_status == true) {
 			ret = true;
 		}
 		if (ret == false) {
@@ -1685,8 +1736,10 @@ int MySQL_Connection::async_send_simple_command(short event, char *stmt, unsigne
 	}
 	if (async_state_machine==ASYNC_QUERY_END) {
 		if (mysql_errno(mysql)) {
+			compute_unknown_transaction_status();
 			return -1;
 		} else {
+			unknown_transaction_status = false;
 			async_state_machine=ASYNC_IDLE;
 			return 0;
 		}