PHP Fatal error: Call to undefined function mysql_connnect() in /var/www/html/mysqltest.php on line 2
yum install php-mysql
安装后重启apache即可
如果还不行，可将mysql.so和mysqli.so添加到php.ini文件中
Call to undefined function mysql_connnect()
原文：http://www.cnblogs.com/rwxwsblog/p/5252177.html