The Nagios web interface always offers a menu in the left-hand frame, and current information is shown in the remaining area. You can easily access all views from the left-hand menu.

In case you want to replace the standard Nagios welcome screen with your own, all that's needed is to change the /opt/nagios/share/main.php file. As this page is shown to everyone after they log in correctly, it can be used to provide administrators with some guidelines on how Nagios monitoring is used within their company and what should be done in certain circumstances. It can also be used to define links to commonly checked hosts or commonly accessed services.

It is also possible to extend the left-hand menu, which is defined in the side.php file located at /opt/nagios/share/. This way, quick links can be added to the menu and/or unused functionalities can be removed from it.

Throughout the rest of this chapter, we will use configuration that is far more complex than the one we created...