Re: Cannot get IPv6 router working

["Steven M. Bellovin" <smb%cs.columbia.edu@localhost>]

On Tue, 30 Jun 2009 19:30:57 -0400
"Brian A. Seklecki" <seklecki%noc.cfi.pgh.pa.us@localhost> wrote:

> On Tue, 2009-06-30 at 21:10 +0100, Roy Marples wrote:
> > I get an inet6 fe80: address on pppoe0 which indicates IP6CP worked.
> 
> Shouldn't your WAN interface get IP space in 2000::/3 (via NDP or
> PPPoE)?
> 
> FE80::/10 is reserved by IANA for link-local (autoconfig).
> 
> I don't see it being able to actually route.
> 
> Also, what /64 are you handing out to your ath0/LAN interface?  Are
> you handing it out via rtadvd(8)?  What does rtadvd.conf(5) look like?
> 
I'm having rtadvd troubles, too, with or without rtadvd.conf.

tcpdump shows the messages being received, on both another NetBSD box
and a Mac.  Neither is creating non-link-local addresses with the
advertised prefix.  Both machines have correctly used v6 elsewhere.
Yes, I have the NetBSD box (both the advertiser and receiver are
running very recent -current) configured to accept router
advertisements:

        net.inet6.ip6.accept_rtadv = 1

Here's a tcpdump of the received message, with the addresses edited for
privacy:

21:26:30.393860 IP6 (hlim 255, next-header: ICMPv6 (58), length: 56) 
fe80::211:xxxx:xxxx:xxxx > ff02::1: [icmp6 sum ok] ICMP6, router advertisement, 
length 56
        hop limit 64, Flags [none], pref medium, router lifetime 1800s, 
reachable time 0s, retrans time 0s
          source link-address option (1), length 8 (1): 00:yy:yy:yy:yy:yy
            0x0000:  00yy yyyy yyyy
          prefix info option (3), length 32 (4): 2001:zzz:z:zzz::/56, Flags 
[onlink, auto], valid time 2592000s, pref. time 604800s
            0x0000:  38c0 0027 8d00 0009 3a80 0000 0000 2001
            0x0010:  zzzz zzzz zzzz 0000 0000 0000 0000

Both speak v6 successfully with manually configured v6 addresses on that
net.


                --Steve Bellovin, http://www.cs.columbia.edu/~smb