problem with ipv6 tunneling

[Loic Le Loarer <loic.le-loarer+kernel@xxxxxxxxxxxxxxxxx>]

Hello,

I have a problem when setting up and ipv6 tunnel over ipv4. I am
connected to the Internet with ADSL (pppoed) :
[root@alibaba ~]# ifconfig
eth0      Link encap:Ethernet  HWaddr 00:10:5A:2D:D9:53
          inet6 addr: fe80::210:5aff:fe2d:d953/10 Scope:Link
          UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1
          RX packets:1854 errors:0 dropped:0 overruns:0 frame:0
          TX packets:2007 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:100
          RX bytes:1460764 (1.3 Mb)  TX bytes:333600 (325.7 Kb)
          Interrupt:10 Base address:0xe400

lo        Link encap:Local Loopback
          inet addr:127.0.0.1  Mask:255.0.0.0
          inet6 addr: ::1/128 Scope:Host
          UP LOOPBACK RUNNING  MTU:16436  Metric:1
          RX packets:1830 errors:0 dropped:0 overruns:0 frame:0
          TX packets:1830 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:0
          RX bytes:160533 (156.7 Kb)  TX bytes:160533 (156.7 Kb)
 
ppp0      Link encap:Point-to-Point Protocol
          inet addr:195.154.54.178  P-t-P:195.154.54.129
Mask:255.255.255.255
          UP POINTOPOINT RUNNING NOARP MULTICAST  MTU:1492  Metric:1
          RX packets:1781 errors:0 dropped:0 overruns:0 frame:0
          TX packets:1924 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:3
          RX bytes:682362 (666.3 Kb)  TX bytes:286164 (279.4 Kb)

The ifconfig sit0 up command works well and adds this to ifconfig result :
sit0      Link encap:IPv6-in-IPv4
          inet6 addr: ::195.154.54.178/96 Scope:Compat
          inet6 addr: ::127.0.0.1/96 Scope:Unknown
          UP RUNNING NOARP  MTU:1480  Metric:1
          RX packets:0 errors:0 dropped:0 overruns:0 frame:0
          TX packets:0 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:0
          RX bytes:0 (0.0 b)  TX bytes:0 (0.0 b)

but when I try to configure this tunnel with I get :
[root@alibaba ~]# ifconfig sit0 tunnel ::206.123.31.102
SIOGIFINDEX: Bad file descriptor
[root@alibaba ~]# ifconfig eth0 add 3ffe:b00:c18:1fff:0:0:0:6df
SIOGIFINDEX: Bad file descriptor
[root@alibaba ~]# ifconfig sit1 up
sit1: unknown interface: No such device

Can you help me, please ?
Do you have and idea of the meaning of such and error ?
-- 
Loïc

mel : loic.le-loarer@xxxxxxxxxxxxxxxxx
toile : http://www.le-loarer.org/

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