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i'm trying to get Teredo to function on my machine.

Most routers, it seems, refuse to forward packets from any host other than the one i specifically connected to first. Teredo requires full Cone NAT in order to function.

Does any router, hardware or software, allow full cone NAT?

Is this an oversight by the designers of Teredo that nobody, in practice, can use it?

i've tried

  • m0n0wall
  • pfsense
  • D-Link
  • Linksys
  • SMC
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Some routers have a "gaming mode" that will turn on full cone NAT

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I've never had Teredo fail behind any NAT, even dodgy old Checkpoint.

I don't have much more info then that as all the Linux NAT's I use now have 6to4 enabled and advertised giving native IPv6 to clients.

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6to4 on the router itself. i never actually thought about that. Although, the hope is that a machine behind the firewall gets to appear as though it's directly connected to the internet - bypassing all firewall rules. – Ian Boyd Aug 7 '09 at 17:20

According to this post, in a 1-1 scenario maybe SNAT and DNAT will be sufficient in netfilter to make a full cone nat.

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