It’s always a good idea to test your newly updated Apache config file before restarting the service itself. This will help avoid downtime due to Apache refusing to start due to misconfiguration. You can use apachectl, httpd or equivalent binaries as in the examples below;

Different platform might use different binary names such as apache, apache2 or apache2ctl

  1. httpd

    # httpd -t
AH00112: Warning: DocumentRoot [/var/www/mywebsite] does not exist
AH00558: httpd: Could not reliably determine the server's fully qualified domain name, using 127.0.0.1. Set the 'ServerName' directive globally to suppress this message
Syntax OK

  2. apachectl

    # apachectl configtest
AH00112: Warning: DocumentRoot [/var/www/mywebsite] does not exist
AH00558: httpd: Could not reliably determine the server's fully qualified domain name, using 127.0.0.1. Set the 'ServerName' directive globally to suppress this message
Syntax OK

What happens is that the programs will try to parse the configuration files without implementing any of your changes. Once you get Syntax OK at the end of the output and are satisfied with all the warnings (if any), you could confidently restart your Apache service.

How to restart Apache service