Apach2 returns "qualified domain name" message

If an apache server has no domain name, it returns the following message. It isn't bad messages, but I don't want to see this message. After googling, the solution is ..

# /etc/init.d/apache2 restart
[....] Restarting web server: apache2apache2: Could not reliably determine the server's fully qualified domain name, using 192.168.101.24 for ServerName
 ... waiting apache2: Could not reliably determine the server's fully qualified domain name, using 192.168.101.24 for ServerName
. ok
# cd /etc/apache2/conf.d/
# echo "ServerName localhost" >> name
root@jhleepc:/etc/apache2/conf.d# service apache2 restart
[ ok ] Restarting web server: apache2 ... waiting .