2002: IP for my "auto config" IPv6 tunnel?

[dherr]

Howdy all....

I was given a Netgear wnr2000v3 and while setting it up I realized that it could do Ipv6, so I futzed about with it and it actually worked:

15:12-doug@wombat-~>ping6 -nc2 ipv6.google.com
PING ipv6.google.com(2607:f8b0:4010:800::1007) 56 data bytes
64 bytes from 2607:f8b0:4010:800: icmp_seq=1 ttl=57 time=24.2 ms
64 bytes from 2607:f8b0:4010:800: icmp_seq=2 ttl=57 time=23.6 ms

--- ipv6.google.com ping statistics ---
2 packets transmitted, 2 received, 0% packet loss, time 1001ms
rtt min/avg/max/mdev = 23.613/23.909/24.205/0.296 ms

Now for the odd part. I used the auto config options of the router and it gave me:
Router's IPv6 Address On WAN: 2002:ade4:1/16

Router's IPv6 Address On LAN
2002:ade405dff:fe8f:f880/64

And as you see with that ping, it *is* working. But the Sonic Ipv6 tunnel info that the lab tool gives me is using 2001, not 2002 address space:
Transport:: 200100000000:0000:0000:1a1a/127
Network:: 20010004:d0d0:0000:0000:0000:0000/60

I am happy that it seems to be working (tested from Fedora, Windows, oldWindowsXP in a VirtualBox).

But I do fear that I am doing something "wrong" by using that IP space instead of what the lab tool shows as being assigned to me.

Any clues out there?

[geogriffin]

i believe the situation is:

the 2002 address is from the 2002::/16 allocation for 6to4 address translation. ade4:27fe corresponds to your public ipv4 address.

the 2001 address is from the 2001:5a8::/32 direct allocation for sonic, which they use to give your tunnel endpoint a specific address independent of your ipv4 address. get used to having many ipv6 addresses per box..

[dherr]

Ah yes, that helps a lot, thanks much. I googled "calculate ipv6 tunnel address" and found:
http://www.wyae.de/docs/ipv6calc/

Sure enough; when I enter my static ipv4 address it gives me the same 6to4 tunnel address that I ended up with. So I guess my router (or the far end maybe) just does this conversion and gets me going. I will keep trying to get the wnr2000v3 to utilize the assigned 2001: address space, but I am happy either way since I can now get to IPv6 only hosts now.

[nsmiller]

In my experience, Netgear routers use either DHCPv6, or 6to4, but not 6in4, or 6rd. I played with a couple, and could not find a way to configure either my Hurricane Electric 6in4 tunnel (2001:470448::/64), or my Sonic.net 6in4 tunnel (2001:5a8:4:a4f0::/60).

Other routers, that I know of, which can use 6in4 and 6rd, in addition to DHCPv6 and 6to4 are ASUS and D-Link.

It is likely that third-party firmware on Netgear routers will offer 6in4 and 6rd capability.