Could not reliably determine the server's fully qualified domain name?

ubuntu 12.04 and older This is just a friendly warning and not really a problem (as in that something does not work). If you insert a ServerName localhost in either httpd.conf or apache2.conf in /etc/apache2 and restart apache the notice will disappear. If you have a name inside /etc/hostname you can also use that name instead of localhost. And it uses 127.0.1.1 if it is inside your /etc/hosts: 127.0.0.1 localhost 127.0.1.1 myhostname Preferred method Troubleshooting Apache If you get this error: apache2: Could not determine the server's fully qualified domain name, using 127.0.0.1 for ServerName then use a text editor such as "sudo nano" at the command line or "gksudo gedit" on the desktop to create a new file, sudo nano /etc/apache2/conf.d/fqdn or gksu "gedit /etc/apache2/conf.d/fqdn" then add ServerName localhost to the file and save. This can all be done in a single command with the following: echo "ServerName localhost" | sudo tee /etc/apache2/conf.d/fqdn But on Ubuntu 14.04: echo "ServerName localhost" | sudo tee /etc/apache2/conf-available/fqdn.conf sudo ln -s /etc/apache2/conf-available/fqdn.conf /etc/apache2/conf-enabled/fqdn.conf Don't forget the ".conf" (without will not work).