At the very beginning of installation of rocks-7.0, we must define a roll server. It's recommended to set up a local server to facilitate roll addition. There are some scripts to make this easy for non experts here. After doing steps 0, I and II, change your site configuration file (e.g /etc/apache2/sites-enabled/000-default.conf in ubuntu or mint) to be like this:
## Definitions for rocks-7-0.my.org (change according to your one)
###
<VirtualHost *:80>
ServerName rocks-7-0.my.org
</VirtualHost>
# allow all access to the rolls RPMS