If you get this error everytime apache starts you should take this action. I had a default install of ISPConfig and had this issue.
Edit /etc/httpd/conf/httpd.conf and httpd.conf1
# added servername to avoid the could not determine fully qualified domain name
For example :
Here is how to fix :
Starting httpd: httpd: Could not reliably determine the server’s fully qualified domain name.
You might get this error when restarting Apache. To resolve the issue add the following to your httpd.conf file:
The file is usually located at – /etc/httpd/conf/httpd.conf
I use the same information that is in my reverse dns to my main public server IP.