CentOS change MySQL data store file location

Problem:

1, there was a problem [[email protected] mysql]# service mysql restart
mysql Server PID file could not be found! [Failed]
starting MySQL ... The server quit without updating PID file (/usr/local/mysql/data/rekfan.pid). [Failed]

My solution:

/usr/local/mysql/data/rekfan.pid file does not have write permission
Workaround: Give permission, execute  " CHOWN  - r mysql : MYSQL  / var / data "  " chmod-r 755/ Usr/local/mysql/data "   then restart mysqld!

Some of the possible solutions offered online are:

1. The/usr/local/mysql/data/rekfan.pid file may not have write permission
Workaround: Give permission, execute   "CHOWN  Span class= "pun" >- r mysql : mysql  / var / data "   Chmod-r 755/usr/local/mysql/data    and then restart the mysqld!

2. The MySQL process may already exist in the process
WORKAROUND: Use the command "Ps-ef|grep mysqld" to see if there is a mysqld process, kill with "kill-9 process number" and then restart mysqld!

3. It may be the second time that MySQL is installed on the machine, with residual data affecting the start of the service.
workaround: Go to MySQL data directory/data See, if there is mysql-bin.index, quickly delete it, it is the culprit. I am using the third method to solve! http://blog.rekfan.com/?p=186

4.mysql The/ETC/MY.CNF profile is used when the configuration file is not specified at startup, please open this file to see if there is a specified data directory (DATADIR) under the [Mysqld] section.
WORKAROUND: Please set this line under [mysqld]: DataDir =/usr/local/mysql/data

5.skip-federated Field Issues
Workaround: Check the/etc/my.cnf file for any skip-federated fields that have not been commented out, and if so, comment them out immediately.

6. Error log directory does not exist
Workaround: Use "Chown" "chmod" command to give MySQL owner and permissions

7.selinux, if it is a CentOS system, the default is to turn on SELinux
Workaround: Turn it off, open the/etc/selinux/config, change the selinux=enforcing to selinux=disabled, and then save the restart machine and try again.

CentOS change MySQL data store file location