I have manually specified only ipv4 address for my interfaces. But all the interfaces automatically show inet6 address as well. Does it mean that ubuntu starts an ipv6 tunnel by default. If it does, isn't it dangerous, as ipv6 assigns public ips for all LAN clients. I only have a firewall on my NAT router, and my clients, who's interfaces show ipv6 address, do not have firewalls. Here is a screenshot:
eth0 Link encap:Ethernet HWaddr 34:dc:47:2e:ad:13 inet6 addr: fe80::28cf:38ff:fb7b:da19/64 Scope:Link UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1 RX packets:5783 errors:0 dropped:0 overruns:0 frame:0 TX packets:6098 errors:0 dropped:0 overruns:0 carrier:1 collisions:0 txqueuelen:1000 RX bytes:2961324 (2.9 MB) TX bytes:1573757 (1.5 MB) Interrupt:46
Note: For privacy reasons I have modified the
inet6 addr values.