Setup: A VLAN without internetaccess. When a user connects his/her computer with cable and tries to surf, the traffic will be directed to internal website. How can I setup a DNS Wildcard so all traffic maps to internal website?
DNS is not the right tool to achieve your goal IMHO.
This can be better done using the FW, doing a REDIRECT of all outbound traffic on web ports to your local web server, maybe you can consider adopting a transparent Web Proxy too ..
The implementation depends on you configuration, you can find tons of examples on the web; here is the first I got in google looking for iptables redirect