Few days back i have mistakenly deleted one database folder directly from the mysql data directory but still the site was working fine. I just wondering how its working?
So i restarted the mysql service. It stopped but didn’t start and getting below error in the log file
[root@localhost html]# tail -f /var/log/mysqld.log
InnoDB: Error: log file ./ib_logfile0 is of different size 0 84992 bytes
InnoDB: than specified in the .cnf file 0 5242880 bytes!
131001 17:54:45 [ERROR] Plugin ‘InnoDB’ init function returned error.
131001 17:54:45 [ERROR] Plugin ‘InnoDB’ registration as a STORAGE ENGINE failed.
131001 17:54:45 [ERROR] Unknown/unsupported storage engine: InnoDB
131001 17:54:45 [ERROR] Aborting
131001 17:54:45 [Note] /usr/libexec/mysqld: Shutdown complete
131001 17:54:45 mysqld_safe mysqld from pid file /var/run/mysqld/mysqld.pid ended
As usual i started searching google and didn’t find any solution and final got one solution. It’s to delete the ib_logfile0, and i deleted it and trying to start the mysql service and it start working by recreating this file automatically…
What i understand from this, if you going to re-install the mysql or wamp server and to take backup of these databases, you have to follow below instructions,
- First stop the mysql service
- Copy the database which you need to have backup from the mysql data directory
- Re-install / Install either Mysql or Wamp Server
- Stop the mysql service
- Paste the database backup in the mysql data directory which you have taken previously
- Start the mysql service
This will keep the old database backup easily without any problem and this will avoid importing the database again. May be imporing small database is not a problem, but thing when you have some 1GB or @ GB size of db, then it will take more time to import the database. Following the above steps, will save your time.