nagios2 add-on



I’m new here and this problem. I’ve installed nagios2 on ubuntu server 8.04, a standard install without any extra plugins or add-ons.
Now, what I already did is created a host.cfg file what a few windows servers. On the server I’ll going to monitor, nsclient++ is alreay installed. This information I found on the website
Now my problem, what do I have to configure at serverside? (server were nagios is installed on)
Can anyone help me with this problem, so I can move on?