How to fix Apache – “Could not reliably determine the server’s fully qualified domain name, using 127.0.1.1 for ServerName” Error on Ubuntu

“Could not reliably determine the server’s fully qualified domain name, using 127.0.1.1 for ServerName“. I get this error upon restarting Apache Server on a server running Ubuntu 16.04. This occurs because the ServerName is not set.

sudo systemctl restart apache2

AH00558: apache2: Could not reliably determine the server's fully qualified domain name, using 127.0.1.1. Set the 'ServerName' directive globally to suppress this message

To fix this problem, we need to edit the apache2.conf file. Open the terminal and type this command:

sudo nano /etc/apache2/apache2.conf

However, at the very bottom of that file and add this line:

ServerName localhost

This should solve the problem and the error code AH00558 should now be gone. Now restart Apache server using the following command:

sudo systemctl restart apache2

I hope this article helps.

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