Virtual Hosts created on the Cornell Stack can be configured to allow your own Apache virtualhost include file that will be used by an instance. This feature can cause a site to become unavailable if mis-configured.
This is recommended for ADVANCED users only that are comfortable with Apache configurations and changing server settings that may affect the stability of a website.
The Apache Foundation website is an excellent resource on how the web server can be configured.
How it works
When a VirtualHost is configured to allow a custom VirtualHost include (not on by default) you will see a new directory under your "instance" directory at the same level as your "htdocs" folder.
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