(usagi-users 03510) How to create an ip6-in-ip6 tunnel and ip4-over-ip6 tunnel in linux ??

Hi to all,

can anyone please let me know how to create an ip6-in-ip6 tunnel 
and ip4-over-ip6 tunnel in linux. is these tunnels are supported by
iproute2 tool?? please let me know the command or any document 
which I should refer , if anyone of you have worked 
on this.

thanks and regards

Pramendra Singh
Larsen and Toubro Infotech 

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