This mysqlnd extension handle load balancing betwwen master and slave servers, handled by the application, or transparently.

Pecl site: mysqlnd_ms

Documentation : Mysqlnd replication and load balancing plugin

Fedora review : Review request #742729

Installation, after the switch from php-mysql to php-mysqlnd :

yum --enablerepo=remi install php-pecl-mysqlnd-ms

RPM are available for fedora >= 10 and EL >= 4.