Roundcube is a webmail client.
The ideal situation is that you install Roundcube via the paid app.
" By purchasing this app in the Marketplace, you help support eGloo developers maintain this app and build new ones. In addition, US $5 of every app purchase will be given to the Roundcube developers to help support their efforts in providing a simple and easy-to-use Webmail client for use on premise or in a hosted cloud environment."
But if you can't (or if this is just for testing)
Note: these instructions are incomplete
you can simply install Roundcube (with fewer features than the app) with:
yum --enablerepo=clearos-contribs install roundcubemail
Once installed, the app will be available in /usr/share/roundcubemail directory and an Apache configlet will exist in /etc/httpd/conf.d/ called roundcubemail.conf.
You will need to go through the configuration manually. To start, rename the hidden .installer directory:
mv /usr/share/roundcubemail/.installer /usr/share/roundcubemail/installer
and navigate to:
Where x.x.x.x is your server's IP/hostname.
You will need to create a MariaDB or MySQL database. Ex.: via the command line or Adminer