When a MariaDB Galera cluster node fails to apply a binary log (or writeset, as we call it), the node dumps it into a file (GRA_X_X.log) under the data directory for further investigation. This process has been explained fairly well in this Percona blog). Since the dumped log file is header-less, one has to first prepend a binary log header to it in order to open it using mysqlbinlog tool.
Starting MariaDB 10.1.4, the node will automatically prepend the binlog header to the writeset before dumping it into the GRA_ log file. In order to differentiate it from the older log files, the file has been renamed to GRA_X_X_v2.log.
$ ./bin/mysqlbinlog data2/GRA_1_1_v2.log /*!50530 SET @@SESSION.PSEUDO_SLAVE_MODE=1*/; /*!40019 SET @@session.max_insert_delayed_threads=0*/; /*!50003 SET @OLD_COMPLETION_TYPE=@@COMPLETION_TYPE,COMPLETION_TYPE=0*/; DELIMITER /*!*/; # at 4 #150414 17:50:20 server id 0 end_log_pos 248 Start: binlog v 4, server v 10.1.4-MariaDB-wsrep-debug created 150414 17:50:20 at startup ROLLBACK/*!*/; BINLOG ' nIstVQ8AAAAA9AAAAPgAAAAAAAQAMTAuMS40LU1hcmlhREItd3NyZXAtZGVidWcAAAAAAAAAAAAA AAAAAAAAAAAAAAAAAACciy1VEzgNAAgAEgAEBAQEEgAA3AAEGggAAAAICAgCAAAACgoKAAAAAAAA AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA AAAAAAAAAAAEEwQAZxODxw== '/*!*/; # at 248 #150414 17:50:20 server id 0 end_log_pos 76 Query thread_id=4 exec_time=0 error_code=0 use `test`/*!*/; SET TIMESTAMP=1429048220/*!*/; SET @@session.pseudo_thread_id=4/*!*/; SET @@session.foreign_key_checks=1, @@session.sql_auto_is_null=0, @@session.unique_checks=1, @@session.autocommit=1/*!*/; SET @@session.sql_mode=0/*!*/; SET @@session.auto_increment_increment=1, @@session.auto_increment_offset=1/*!*/; /*!\C utf8 *//*!*/; SET @@session.character_set_client=33,@@session.collation_connection=33,@@session.collation_server=8/*!*/; SET @@session.lc_time_names=0/*!*/; SET @@session.collation_database=DEFAULT/*!*/; drop table t1 /*!*/; DELIMITER ; # End of log file ROLLBACK /* added by mysqlbinlog */; /*!50003 SET COMPLETION_TYPE=@OLD_COMPLETION_TYPE*/; /*!50530 SET @@SESSION.PSEUDO_SLAVE_MODE=0*/;