problem

mysqlbinlog -v -v --base64-output=DECODE-ROWS mysql-bin.000166 | less

ERROR: Error in Log_event::read_log_event(): 'Found invalid event in binary log', data_len: 111, event_type: 35
/*!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
#190408 18:15:19 server id 311948559  end_log_pos 123 CRC32 0x56e12e5d  Start: binlog v 4, server v 5.7.21-log created 190408 18:15:19
# Warning: this binlog is either in use or was not closed properly.
BINLOG '
Nx+rXA8P9ZcSdwAAAHsAAAABAAQANS43LjIxLWxvZwAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA
AAAAAAAAAAAAAAAAAAAAAAAAEzgNAAgAEgAEBAQEEgAAXwAEGggAAAAICAgCAAAACgoKKioAEjQA
AV0u4VY=
'/*!*/;
DELIMITER ;
# End of log file
ROLLBACK /* added by mysqlbinlog */;
/*!50003 SET COMPLETION_TYPE=@OLD_COMPLETION_TYPE*/;
/*!50530 SET @@SESSION.PSEUDO_SLAVE_MODE=0*/;

View the location of the mysqlbinlog file currently in use

which mysqlbinlog
/usr/bin/mysqlbinlog

ll /usr/bin/mysqlbinlog
-rwxr-xr-x 1 root root 3259000 6 Month 102014 /usr/bin/mysqlbinlog
this myqlbinlog It already exists in 2014 and presumably comes with the machine. mariadb Medium

Version information

/usr/bin/mysqlbinlog --version
/usr/bin/mysqlbinlog Ver 3.3 for Linux at x86_64
/usr/bin/mysqlbinlog Ver 3.3 for Linux at x86_64
Copyright (c) 2000, 2013, Oracle, Monty Program Ab and others.

Dumps a MySQL binary log in a format usable for viewing or for piping to
the mysql command line client.

View the currently running mysqld process basedir

ps -ef | grep defaults | grep 3308 | awk '{print $8}'
/opt/mysql/base/5.7.21/bin/mysqld

Version information

/opt/mysql/base/5.7.21/bin/mysqlbinlog -V
/opt/mysql/base/5.7.21/bin/mysqlbinlog Ver 3.4 for linux-glibc2.12 at x86_64

Delete the original executable mysqlbinlog and re-establish the soft link

rm -r /usr/bin/mysqlbinlog
rm: Whether to Delete Ordinary Files "/usr/bin/mysqlbinlog"？y

ln -s /opt/mysql/base/5.7.21/bin/mysqlbinlog /usr/bin

It can be used normally.

mysqlbinlog -v -v --base64-output=DECODE-ROWS mysql-bin.000166 | less

/*!50530 SET @@SESSION.PSEUDO_SLAVE_MODE=1*/;
/*!50003 SET @OLD_COMPLETION_TYPE=@@COMPLETION_TYPE,COMPLETION_TYPE=0*/;
DELIMITER /*!*/;
# at 4
#190408 18:15:19 server id 311948559  end_log_pos 123 CRC32 0x56e12e5d  Start: binlog v 4, server v 5.7.21-log created 190408 18:15:19
# Warning: this binlog is either in use or was not closed properly.
# at 123

The old version of mysql executable file can run normally

ll /usr/bin/mysql
-rwxr-xr-x 1 root root 3546584 6 Month 102014 /usr/bin/mysql

mysql --version
mysql Ver 15.1 Distrib 5.5.35-MariaDB, for Linux (x86_64) using readline 5.1

/opt/mysql/base/5.7.21/bin/mysql -uroot -p --socket=/datas/mysql/data/3308/mysqld.sock -e"select version()"
Enter password:
+------------+
| version() |
+------------+
| 5.7.21-log |
+------------+

conclusion