OK now I understand better how it's done.
If you want to use your own nameserver, you must tell your domain registrar so that he can make the necessary changes.
Here we have a problem because I understand that the nl domains accept this only if I have a master and a slave-server, at two seperate ip-adresses.
I will have to ask my provider if I can have a second ipadress set permanent to my second macadres(networkcard).
Thank you for the reply's