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root@solaris10:~# ifconfig ip.6to4tun0 down
ifconfig: setifflags: SIOCGLIFFLAGS: ip.6to4tun0: no such interface
root@solaris10:~# ifconfig ip.6to4tun0 unplumb
ifconfig: unplumb: SIOCGLIFFLAGS: ip.6to4tun0: no such interface
A resposta curta será "não existia!" mas...
root@solaris10:~# ifconfig -a|ggrep -A 11 6to4
ip.6to4tun0: flags=2200041<UP,RUNNING,NONUD,IPv6> mtu 65515 index 9
inet tunnel src 192.168.0.1
tunnel hop limit 60
inet6 fe80::203:baff:fe50:cbe6/128
A interface funciona
ping 192.168.0.1
192.168.0.1 is alive
ping -A inet6 fe80::203:baff:fe50:cbe6
fe80::203:baff:fe50:cbe6 is alive
Solução encontrada
Esses comandos
são para ipv4
para ipv6 devemos usar isso