In my scenario, the Apache server doesn’t need to be aware that it is only one server of many. Therefore I’ve customised my configuration file and copied the exact same file to all 3 servers. How much you customise is down to taste and requirements, but at a minimum I would suggest disabling any modules that you don’t need, configuring a ServerAdmin address and setting up logging to suit your needs.
I’ve posted my somewhat stripped down httpd.conf should you wish to use it as a starting point (it’s for Apache 2.2 on CentOS 5).
In addition to the customisations to httpd.conf, take a look in /etc/httpd/conf.d/ to see what other files are being loaded. I removed the welcome.conf file, but didn’t make any further changes. Most Apache modules will install a config file here, for example mod_ssl will create an ssl.conf file here.
Finally, enable the apache service:
chkconfig httpd on service httpd start