IPv6-PD update fails with dynamic IPv6 address

Dear all,

my provider gives me a dynamic IPv6 address (dynamic /56 prefix)
I receive it on my first router, an AVM Fritz!Box 7490.

Behind this router, I have an OpenWrt firewall (21.02.2) which receives a /62 IPv6-PD.

When my /56 prefix changes, I expected the IPv6-PD to adjust automagically.

...which it doesn't

The only change is that wan6 receives an updated /128 address for itself.
However, the /62 IPv6-PD remains unchanged.

Could it be that this is a bug?

In theory odhcpd should handle this. According to @slh it's even a major reason why odhcpd exists: What is the role of odhcpd / dnsmasq ? - #22 by slh

However, I never got dynamic prefixes working with OpenWrt, sadly.

I had a similar setup you describe and I can remember that I wrote an ugly script that restarted the WAN6 interface when the IPv6 address of the Fritzbox changed (which was polled via TR-064). That was really messy but did the trick. Unfortunately I don't seem to have this script anymore.

Yea - that's also my own workaround.
However, initially, this isn't supposed to be the way - is it?

No, definitely not.
You're right, it's most likely a bug. I vaguely remember that there was also a flyspray ticket - I'll have to see if I can still find that.

I just opened a ticket @github.

@sebastian_de: Thank you for the confirmation.

You're welcome.
Please post the link to the github issue here.


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