MACROMEDIA FLASH MEDIA SERVER 2-MANAGING FLASH MEDIA SERVER Manual page 68

If there is a second adaptor, it has its own subdirectory at the same level as the
_defaultRoot_ subdirectory.
The _defaultVHost_ subdirectory is the default virtual host subdirectory for the adaptor.
It contains the Application.xml file, which contains default settings for the client
applications that will connect to the server; the Vhost.xml file, which contains the settings
for the virtual host; and the Users.xml file, which defines the administrative users and
their permissions for the Flash Media Admin Service.
The Users.xml file is required only if you are defining administrators for this virtual host.
If there is another virtual host on the same adaptor, it has its own subdirectory at the same
level as the _defaultVHost_ subdirectory.
68 Deploying Flash Media Server