CentOS - Plesk / "This site can’t be reached"

Hi,

I just purchased a brand new VPS here, and a fresh CentOS 7 install.

I installed wget, and ran the plesk installation wget:

cd /usr/local/src
wget -O – http://autoinstall.plesk.com/one-click-installer | sh

Now I have to access http://HOSTNAME:8443 in order to complete the plesk install, but I just get "This site can’t be reached
HOSTNAME took too long to respond." when (of course) replacing it with my public IP.

First time ever using Linux, so no idea why and how, heh..