How to set some SELinux bools permanent to true?

 By default, the httpd_can_network_connect_db Boolean is off, preventing Apache HTTP Server scripts and modules from connecting to database servers. If your Apache HTTP server requires access to external database server the value muse be 'on'.

To check status: 

# sestatus -b

To set value to 'on' permanently, execute the following command:

# sudo setsebool -P httpd_can_network_connect_db on

-P to make it Permanently changed