Root-directory
From Resin 3.0
The <root-directory> directive specifies the root of the current Environment. In a <host>, it specifies the parent directory for any <access-log>, <web-app-deploy>, or any child <web-app>.
<host>
In general, you should configure a <root-directory> for each virtual host.
If you deploy your virtual hosts with <host-deploy>, then the <root-directory> is already configured for you.