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Mysql/MariaDB Recovery.

[DB_NAME]: DB-name to recovery.

/dev/shm Usage: First, check your memory if you can use shm directory.

  For recovery speed, I use /dev/shm/ directory.


Process flow.

01. Stop DB

 service mysqld stop

02. Stop web-service. (If you don't use, block DB-connection by using firewall-cmd.)

 service httpd stop

03. Change DB-mode on server.cnf 

 set innodb_force_recovery = 5 on /etc/my.cnf.d/server.cnf

04. Start DB for recovery.

 service mysqld start

05. Run DB-dump.

 mysqldump -u root -p --databases [DB_NAME] > /dev/shm/[DB_NAME].sql

06. Stop DB

 service mysqld stop

07. Change DB-mode on server.cnf (normal mode)

 set innodb_force_recovery = 0 on /etc/my.cnf.d/server.cnf

08. Backup old DB-files. (Run follows if you necessarily need backup.)

 mkdir /backup/DB_BackupTmp

 mv /backup/DB/ibdata1 /backup/DB_BackupTmp

 mv /backup/DB/ib_logfile0 /backup/DB_BackupTmp

 mv /backup/DB/ib_logfile1 /backup/DB_BackupTmp

 mv /backup/DB/[DB_NAME] /backup/DB_BackupTmp

09. Start DB

 service mysqld start

10. Create Database: [DB_NAME]

 mysql -u root -p

 CREATE DATABASE [DB_NAME];

11. Recover DB-dump

 mysql -uroot -p [DB_NAME] < /dev/shm/[DB_NAME].sql

12. Start web-service. (If you don't use, change DB-connection for allow by using firewall-cmd.)

 service httpd start


-End-


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