# 将安装目录属主改为mysql[上面更改，到这里又变成root属主了，所以可以选择更改为mysql]
[root@client100 support-files]#chkconfig --add mysqld
[root@client100 support-files]#chkconfig mysqld on
[root@localhost support-files]# chkconfig --list |grep mysql --234必须为on
[root@client100 support-files]#service mysqld start
[root@client100 support-files]#echo "drop user 'root'@'::1';drop user ''@'localhost';drop user 'root'@'localhost.localdomain';"|mysql
[root@client100 support-files]#mysqladmin -u root password '123456'
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如果起数据库报错多半不外乎两种可能
第一种是你[root@localhostsrc]#./mysql_install_db--user=mysql --datadir=/data/mysql/data --basedir=/usr/local/mysql路径不对那么重新执行这句
第二种则是你有老的数据库没有关闭或者你多次service mysqld start导致的。解决办法如下
[root@localhost support-files]# service mysqld restart
ERROR! MySQL server PID file could not be found!
Starting MySQL.. ERROR! The server quit without updating PID file (/data/mysql/data/localhost.localdomain.pid).
[root@localhost support-files]# ps -ef |grep mysql
root 47388 1 0 17:03 pts/0 00:00:00 /bin/sh /usr/local/mysql/bin/mysqld_safe --datadir=/data/mysql/data --pid-file=/data/mysql/data/localhost.localdomain.pid
mysql 47503 47388 0 17:03 pts/0 00:00:00 /usr/local/mysql/bin/mysqld --basedir=/usr/local/mysql --datadir=/data/mysql/data --plugin-dir=/usr/local/mysql/lib/plugin --user=mysql --log-error=/data/mysql/data/localhost.localdomain.err --pid-file=/data/mysql/data/localhost.localdomain.pid
root 62679 11100 0 22:06 pts/0 00:00:00 grep mysql
[root@localhost support-files]# kill -9 47503
[root@localhost support-files]# service mysqld restart
ERROR! MySQL server PID file could not be found!
Starting MySQL.. SUCCESS!