As noted by arco444, you can use apachectl -S to display an overview of the VirtualHosts currently running from the configs, and apachectl -M to display all currently loaded modules – I’m not aware of a tool to display the verbose output of all configs parsed (and which order they were parsed in) at launch of httpd, but I would recommend that you familiarise yourself with the general structure of the httpd config files:
- Apache 2.2 – General structure of the httpd config files
- Apache 2.4 – General structure of the httpd config files
Of particular note to your question: the ‘main’ apache config file is located in /etc/httpd/conf/httpd.conf (in the region of line 221 on a default httpd installation from the repos included in CentOS 6, which I assume you are using based on your post tags), and the ‘supplementary’ config files are located in /etc/httpd/conf.d and require to be included explicitly in the main config file. For example, if you search the httpd.conf file for the term ‘Include‘, you will find the line Include conf.d/*.conf which is what includes all files of extension .conf in the subdirectory conf.d – in alphabetical order, so you will want to familiarise yourself with the importance of config file parsing at some point if possible.
As an aside, if you are using a shell based text editor such as vim, I suggest that you enable line numbering and syntax highlighting by default so that such lengthy config files are a bit easier to parse yourself and navigate – in the case of vim, you’d do so by creating a file in your home directory called .vimrc (or append to an existing one) and add the following lines:
set nu
syntax on