in ghost cms linux centos selinux ~ read.

Ghost CMS + SELinux

Easy way to deal with SELinux blocking Your ghost blog port (or other app).

Check on what port Your app is listening: netstat -tulpn

Check what http ports are allowed by SElinux: semanage port -l | grep http

Add Your port to SELinux: semanage port -a -t http_port_t -p tcp 123

Of course, if that port is closed on firewalld, no one will get access to it from outside.

That is it ;).