MySql在初始化数据库时，有时候会失败，并无法启动数据库，此时kill掉进程，并执行chown授权数据目录即可

问题现象

[root@eoLinker-test scripts]# service mysql start
Starting MySQL.. ERROR! The server quit without updating PID file (/appdata/mysql/data/mysql.pid).
[root@eoLinker-test scripts]# ./mysql_install_db --defaults-file=/etc/my.cnf --basedir=/app/mysql --datadir=/appdata/mysql/data --user=mysql
Installing MySQL system tables...2018-04-27 15:19:23 0 [Warning] 'THREAD_CONCURRENCY' is deprecated and will be removed in a future release.
2018-04-27 15:19:23 0 [Warning] TIMESTAMP with implicit DEFAULT value is deprecated. Please use --explicit_defaults_for_timestamp server option (see documentation for more details).
2018-04-27 15:19:23 0 [Note] /app/mysql/bin/mysqld (mysqld 5.6.26-log) starting as process 19130 ...

解决方案

# chown -R mysql:mysql /appdata/mysql/