I'm using JBoss AS 7.1 Final with mod_cluster 1.2.0.
I've configured HTTPD as follows: http://pastebin.com/C1rnWc1U
However when I try to reach the page http://10.0.0.6:10001/mod_cluster-manager/ it returns a blank page: https://i.stack.imgur.com/9Rl8u.jpg
Answer
That is correct. Unless there are worker nodes connected, there is nothing to display.
Do not use vulnerable code
Please, do not use mod_cluster 1.2.0 with your Apache HTTP Server. The version is completely obsolete and it contains serious bugs, including a code injection CVE and severe performance issue. Download mod_cluster 1.3.1.Final for httpd 2.4.x or build your own from the sources, if you desire httpd 2.2.x support. If you happen to need any any help with that, ask.