Check that the httpd daemon is running by using the following command:
As root user
systemctl status httpd.service
The following result is expected:
● httpd.service - The Apache HTTP Server
...
Active: active (running) since mar. 2018-11-13 10:41:36 UTC; 3h 42min ago
...
The PID number is randomly assigned to an operation and does not have to match the documentation.
If httpd is not running, use the following command:
As root user
systemctl start httpd.service