How do I forward IPv6 prefix into thread network to reach CoAP server?

[Caspar Friedrich]

Hi, I currently try to build a little thread network with a border router bridging to ethernet. I did everything like in the Border Router Quick Start Guide and as far as I can say, everything works fine. My problem is now that I need to reach the CoAP server from outside via IPv6. Is there a 'simple' way to modify your example to forward IPv6 prefixes?

Regards Caspar

[Jørgen Holmefjord]

Do you have IPv6 connection between the boarder router and internet? The boarder router use NAT64 to provide IPv6 prefix to the devices and translating the IPv6 addresses to IPv4. This makes it simple to send messages from the thread network to IPv4 sites on internet, but it does not provide true IPv6 connection. It is not a trivial task to translate incoming IPv4 packages into IPv6 packages for the right device.

[Caspar Friedrich]

Yes, the router has a working IPv6 connection to the internet. I successfully pinged my personal Laptop and the Google DNS via IPv6. The router itself can also ping the Thread devices via IPv6. In the end I don't need 4to6 translation, the local network for my project can be a v6-only network if necessary. I think the only thing I'm missing is the prefix forwarding?

[Jørgen Holmefjord]

In theory, your devices should get a prefix from NAT64 and one prefix from the native connection automatically. Unfortunately, this has not been tested ytes, due to limited access to native IPv6 connection. Could you provide output of ifconfig on the boarder router and ipaddr of one of the CLI devices? You can send me the details in a private message, as the addresses should not be posted publicly on the web.

[Craig]

Even tho this conversation might have continued in a private message can you post the answers here as I'm curious about the same topic, I'm sure others are as well.

[Jørgen Holmefjord]

Yes, we will post the answer here when we confirm what it is. It looks like the problem might be that the router get a IPv6 /64 prefix, while the Thread Boarder Router requires /62 prefix to be able to subnet this network further. Thread requires /64 prefix. We need to do some more testing to see if this is an issue with the boarder router, or the home network/ISP.