MySQL Error! The server quit without updating PID file problem Solving method

Several possible scenarios and solutions

1, may be the/usr/local/mysql/data/mysql.pid file does not have the permission to write
Workaround: Give permission, execute "chown-r mysql:mysql/var/data" "Chmod-r 755/usr/local/mysql/data" and restart 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, may be the second time to install MySQL on the machine, there are residual data affect 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 will use the/ETC/MY.CNF configuration file 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 Problem
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, the disaster of SELinux, if it is a CentOS system, default will open 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.

MySQL Error! The server quit without updating PID file problem Solving method