1) Do you have any other computers behind the Debian box? IE do you have another machine that can help to determine if the Debian box is actually providing DNS and DHCP to the network?
2) From the command line of the Debain box, please post the output of these commands -
ps aux|grep dhcp
dig google.com @localhost
The first command checks for both dhcp and dhcpd processes it is running. The second asks the Debain box for the IP info for the google.com website.
3) If you get positive results from those commands, then try to restart networking on the Suse box.
It is also possible it is just a cable problem that effects the Suse box's connection.