MySQL starting MySQL. The server quit without updating PID file

Possible causes and solutions

1. may be/usr/local/mysql/data/rekfan.pid file does not have permission to write
Workaround: Give permission, execute

chown -R mysql:mysql/var/datachmod755 /usr/local/mysql/data

Then restart mysqld!

2. The MySQL process may already exist in the process
WORKAROUND: Use the command

PS grep mysqld

Check if there is a mysqld process, kill with Kill, and then restart mysqld!

Kill -9  PID

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!

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: Close it

Open/etc/selinux/config to change selinux=enforcing to SELinux=disabled

Quit restarting the machine

8. May be a permissions issue, cannot generate Localhost.localdomain.pid file, modify permissions under/usr/local/mysql/data directory

chmod 777 -R  

MySQL starting MySQL. The server quit without updating PID file