Configuration problem with IPv6 router ("cannot forward src")

Brandon Weisz lists at
Fri Jun 8 15:47:42 UTC 2012

Make sure you are only advertising a /64 addr prefixlen in rtadvd.conf, 
and not the entire /48.

On 6/7/2012 4:36 PM, Bruce Cran wrote:
> I'm trying to set up a IPv6 router (running -current) on my home 
> network. My ISP gives me a /128 via PPP and I have a /48 allocation, 
> which I use to give em0 and tun0 public addresses in different subnets 
> (tun0 is assigned the address via ppp.linkup).
> I've added all the IPv6 settings to rc.conf (ipv6_gateway_enable, 
> ipv6_network_interfaces, rtadvd_enable etc.) and I can ping IPv6 sites 
> from the router.
> The problem is that rtadvd continues advertising the default gateway 
> as tun0's link-local address - and pinging from a machine on the 
> network results in "cannot forward src" messages on the router 
> (strangely, despite hisaddr being fe80::205:... in ppp.log, the kernel 
> logs the address as fe80:f::205:...).
> Is there some extra configuration I've likely missed that's needed 
> when using IPv6 via PPP?

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