Antonio -- If I understand your question properly, you are looking to provide IPv6 connectivity to one of your machines using the "business server" as the gateway (routing using /48 subnet) ? See http://www.sixxs.net/faq/connectivity/?faq=usingsubnet and http://www.sixxs.net/faq/connectivity/?faq=usingsubnet&os=linux.router If you still have problems after following the FAQ, check your firewall(s) to ensure you are not blocking anything you should not, and reply back with what linux distro you are using, and the results of your ifconfig and routing tables and firewall rules while the ipv6 tunnel is up and running. Good Luck. -_Dave

thanks of your answer david. I want to delegate an address ipv6 /128 from my server (where I have shaped the subnet /48) with ip 192.168.1.2 to a posting 192.168.1.5 pre to do I use him it this script that surely is wrong #!/bin / sh / sbin / ip tunnel add tun6to4 mode sit ttl 64 remote 192.168.1.5 locals 192.168.1.2 / sbin / ip link set dev tun6to4 up / sbin / ip -6 addrs add 2001:1418:169::2/128 dev tun6to4 / sbin / ip -6 ro add 2001:1418:169::/48 dev tun6to4 echo "1" > /proc/sys/net/ipv6/conf/default/forwarding echo "1" > /proc/sys/net/ipv6/conf/all/forwarding