How do I configure Apache to run multiple instances?

Specifically, I have two httpd.conf files:

/etc/apache2/httpd.conf

/etc/apache2/httpd_2.conf

How should I modify the /etc/init.d/apache2 script so that instances of Apache will be invoked for both configurations?

The apache2 script is currently standard/unmodified.


see https://serverfault.com/a/397236

alternatively, is it possible to solve your problem with different vhosts?