Foreman and separate Puppet server with Puppet CA

Hi all together,

I want to use a separate Foreman server and attach the Foreman server to our existing Puppet server infrastructure. I got the configuration advice for both servers from the usergroup. It is like this

http://pastebin.com/cBQa5sP9

Additionally I have already read the Foreman documentation under 'Installation scenarios'.

As we are already using a productive Puppet server and I want to keep the Puppet CA on the Puppet server I was wondering if it is possible to keep the Puppet CA on the Puppet Server and still use a separate Foreman server? Or do I require a Puppet CA on the Foreman server?

How would I have to change the configuration option?