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

Question

1. sudo vim /etc/apache2/httpd.conf
2. Insert the following line at the httpd.conf: ServerName localhost
3. Just restart the Apache: sudo /etc/init.d/apache2 restart

Yes, you should set ServerName:

http://wiki.apache.org/httpd/CouldNotDetermineServerName

http://httpd.apache.org/docs/current/mod/core.html#servername

You can find information on the layouts used by the various httpd distributions here:

http://wiki.apache.org/httpd/DistrosDefaultLayout

In your case the file to edit is /etc/httpd/conf/httpd.conf

I was NOT getting the ServerName wrong. Inside your VirtualHost configuration that is causing this warning message, it is the generic one near the top of your httpd.conf which is by default commented out.

Change

#ServerName www.example.com:80

to:

  ServerName 127.0.0.1:80

Under Debian Squeeze;

1. Edit Apache2 conf file : vim /etc/apache2/apache2.conf
2. Insert the following line at the apache2.conf: ServerName localhost
3. Restart Apache2: apache2ctl restart or /etc/init.d/apache2 restart

Should work fine (it did solve the problem in my case)

tks noodl for the link on the different layouts. :)

1. sudo nano /etc/apache2/httpd.conf
2. search for a text ServerName in nano editor <Ctrl + W>
3. Insert the following line at the httpd.conf: ServerName localhost
4. Just restart the Apache: sudo /usr/sbin/apachectl restart

Another option is to ensure that the full qualified host name (FQDN) is listed in /etc/hosts. This worked for me on Ubuntu v11.10 without having to change the default Apache configuration.