httpd_can_network_connect

After upgrading to CentOS 5.3, I discovered that none of my web apps that used MySQL were working. (The test I executed beforehand was not sufficient, since it only connected to localhost.) It turns out that the SELinux policy for these versions of everything were preventing httpd from making network connections. This is corrected with the following command:

setsebool -P httpd_can_network_connect=1

The -P option supposedly applies this change permanently so that it is persistant across reboots.