虚拟机上的cent0s6.2，安装mariadb5.5.20，按照以下步骤安装：
shell> groupadd mysql
shell> useradd -g mysql mysql
shell> cd /usr/local
shell> gunzip < /path/to/mysql-VERSION-OS.tar.gz | tar xvf -
shell> ln -s full-path-to-mysql-VERSION-OS mysql
shell> cd mysql
shell> chown -R mysql .
shell> chgrp -R mysql .
shell> scripts/mysql_install_db --user=mysql
shell> chown -R root .
shell> chown -R mysql data
shell> bin/mysqld_safe --user=mysql &
最后一步报错：
[root@localhost mariadb-5.5.20-linux-x86_64]# bin/mysqld_safe --user=mysql &
[1] 3074
[root@localhost mariadb-5.5.20-linux-x86_64]# 170406 05:10:57 mysqld_safe Logging to '/usr/local/mariadb-5.5.20-linux-x86_64/data/localhost.localdomain.err'.
170406 05:10:57 mysqld_safe Starting mysqld daemon with databases from /usr/local/mariadb-5.5.20-linux-x86_64/data
170406 05:11:00 mysqld_safe mysqld from pid file /usr/local/mariadb-5.5.20-linux-x86_64/data/localhost.localdomain.pid ended
[1]+ Done bin/mysqld_safe --user=mysql
求助，这个百度了好长时间，没找到合适的解决方法。
