If you get next error:
Restarting web server apache2
apache2: Could not reliably determine the server's fully qualified domain name, using 127.0.1.1 for ServerName
... waiting apache2:
Could not reliably determine the server's fully qualified domain name, using 127.0.1.1 for ServerName
Solution:
vi /etc/apache2/conf.d/fqdn
or vi /etc/apache2/conf-available/fqdn.conf ( for Ubuntu 14.04 )
add
ServerName server.domain.org
a2enconf fqdn