Hello,
on a PC with Debian 8 I try to use a Bash script with Netfilter rules so that only traffic goes in and out that is wanted. For that I set all 3 default policies to "drop". The machine uses DHCP to get its IP, gateway and DNS. And I never checked so I was quite surprised that my router/modem assings an IPv6 and not only an IPv4. I wonder if I need additional rules for IPv6. Could somebody explain that problem to me?
Greetings,
SInt
Debian 8.x works a bit more sophisticated on that issue, but check on the GUI your network configurations. Probably there should be an icon where you can disable the IPv6 support and the whole thing. Traffic will not even be started on that. If it works like this, fine, otherwise, try to find the interface in /etc and may comment it out. Hope that helps. Cheers.
Once you have the opportunity to look at the network interfaces and their connections, you can disable or enact them, as well you can set the DNS and the Gateway. The complication of Debian is, that it offers two of that tools.