IPV6

Stuff that I've learnt and found interesting while exploring ipv6



Thompson TG782T
This device does not have any ipv6 support and by default you will not be able to setup a protocol 41 tunnel to a tunnel broker through it, however with a bit of fiddling it is possible.

The first step is to allow the device to respond to icmp echo requests (ping) from the Internet as your tunnel broker (well at least Hurricane Electric) will want to ping your ipv4 adress before attempting to establish the protocol 41 tunnel.
  • telnet to your Thomson router (default details are user:admin password:<blank>)
  • {admin}=>service system ifadd name=PING_RESPONDER group=wan
If you don't want the device to respond to pings from the Internet after the tunnel has been initially established then reboot the router or you can remove it with {admin}=>service system ifdelete name=PING_RESPONDER group=wan . If you do want it to remain through a reboot then issue the {admin}=>saveall command.

This is all that is required, however an interesting "feature" will rear it's ugly head and frustrate you no end unless you do a bit more. Your tunnel will establish and you will be able to ping out from your ipv6 host to the Internet, however you will only be reachable to other hosts on the ipv6 Internet so long as that ping (or any other ipv6 traffic) remains. A few seconds after you stop that ping your router will stop forwarding packets initiated from the ipv6 Internet to you. This is because the router doesn't have a static NAT entry defined. It works fine when you initiate the traffic as it will setup a dynamic NAT entry, however that entry will time out as soon as you stop sending traffic. To fix this you need to setup a static NAT entry.

  • telnet to your Thomson router (default details are user:admin password:<blank>)
  • {admin}=>nat mapadd intf=LocalNetwork type=nat outside_addr=0.0.0.1 inside_addr=10.0.0.7 protocol=6to4
  • {admin}=>nat tmpladd group=wan type=nat outside_addr=0.0.0.1 inside_addr=10.0.0.7 protocol=41 mode=inbound

Ubuntu 12.10

sudo ifconfig sit0 up
sudo ifconfig sit0 inet6 tunnel ::<ipv4 address given to you by your tunnel broker>
sudo ifconfig sit1 up
sudo ifconfig sit1 inet6 add <ipv6 client address given to you by your tunnel broker>
sudo route -A inet6 add ::/0 dev sit1





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