1. InnoDB Stop & MYISAM Start, remove InnoDB redo / tablespace file
vi /etc/my.cnf.d/server.cnf
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# InnoDB disabled
default_storage_engine=MYISAM
#default_storage_engine = InnoDB
# remove InnoDB redo
#innodb_log_buffer_size = 4G
#innodb_log_file_size = 4G
# remove InnoDB tablespace
#innodb_data_file_path = ibdata1:12582912;ibdata2:100G;ibdata3:50G:autoextend
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systemctl restart mariadb.service
2. remove InnoDB redo log files to backup dir., restart with InnoDB
mkdir /var/lib/mysql_backup/
mv /var/lib/mysql/ib_logfile0 /var/lib/mysql_backup/
vi /etc/my.cnf.d/server.cnf
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# InnoDB enabled
#default_storage_engine=MYISAM
default_storage_engine = InnoDB
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systemctl restart mariadb.service