Stop the affected MySQL service and the service plesk-web-socket to prevent it from attempting to start MySQL:
service mysql stop && service plesk-web-socket stop
Back up all the MySQL data storage files. By default, they are located in the directory /var/lib/mysql/ .For example:
cp -a /var/lib/mysql /root/mysql_backup
Add the parameter innodb_force_recovery to the section [mysqld] of the MySQL configuration file. This option allows starting MySQL service in the recovery mode and try creating dumps of databases.For example:
If the service fails to start, set the value of the parameter innodb_force_recovery to a greater value and try starting MySQL again.
Value of the parameter innodb_force_recovery can be from 1 to 6.
Warning: Only set innodb_force_recovery to a value greater than 0 in an emergency situation, so that you can start InnoDB and dump databases. Values of 4 or greater can permanently corrupt data files. Therefore, increase this value incrementally, as necessary. See more details in the official MySQL Documentation.
Very nicely done! I was concerned that the data files were corrupted beyond repair as a result of power failure. The approach you took may have been time consuming , but the knowledge gained may be useful in the future. Don’t forget to save some $$ for a UPS .