let say we have the following picture:
A Apache HTTP server is serving the users' requests. It forwards all (or a part of) requests to a Tomcat server using mod_jk.
Let's say we want to shutdown our application on Tomcat for two hours for maintenance. And we want that all users that access the application get a message about the maintence (Like: sorry, we are maintaining our servers. The app will be online again at 6 a.m.).
Is there a way to put this maintenance page online without restarting the Apache HTTP server? (The server can not be restarting because it is serving other applications)