Got fatal error 1236 from master when reading data from binary log: 'Could not find first log file

解决方法，先到主库查看 binlog和post数值

再到从库修改

change master to master_host='192.168.56.80', master_user='repl', master_password='123456', master_log_file='mysql-bin.000004', master_log_pos=340

再执行

stop slave;

reset slave;

start slave;