How can I allow http access on Centos 7?

By default, the Centos 7 template includes a fully locked down firewall.

To test, you can disable the firewall using

systemctl stop firewalld

To open the firewall for http and https issue the following commands as root, using console or SSH

Allow apache in firewall.

firewall-cmd --permanent --zone=public --add-service=http
firewall-cmd --permanent --zone=public --add-service=https
firewall-cmd --reload