IPv6 prefix delegation over a freebsd router that sits between internet router and local network

[Matthias Fechner]

Dear all,

I have a problem with IPv6 configuration and I'm not sure if it is even
possible.
I'm using an internet connection from mnet (a German internet provider).

The fritzbox 7490 will get an /56 IPv6 prefix that changes every 24 hours.

Behind the fritzbox I have a FreeBSD router with two network interfaces.

Internet
|
Fritzbox 7490 internet interface
Fritzbox 7490 local interface
|
Freebsd interface re0
Freebsd interface em0
|
Internal lan

The network interface in the fritzbox is configured to forward the prefix.
If I check the interfaces the re0 (interface to fritzbox) is getting an
ipv6 address and I can ping6 from the freebsd machine without problems.

But if I try to to ping from a computer in "Internal lan" it fails.
The internal pc resolves the hostname to ipv6 adress but the freebsd
machine shows in /var/log/messages:
Jul  8 20:33:01 server kernel: cannot forward src
fe80:1::88d:dbdc:2c49:ac3a, dst <target-ipv6-address-i-ping>, nxt 58,
rcvif em0, outif re0

So I think I have to forward the delegated prefix to the internal network.
Could maybe anyone point me into the right direction what I have to
configure/read to continue with the setup?

Thanks
Matthias

-- 

"Programming today is a race between software engineers striving to
build bigger and better idiot-proof programs, and the universe trying to
produce bigger and better idiots. So far, the universe is winning." --
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