[6bone] IPv6 Site Multicast

[John Hay]

On Sun, Feb 16, 2003 at 03:44:59PM -0500, Harish Nair wrote:
> 
> Hi,
> 
> I have a question about IPv6 site Multicasting. Our IPv6 network here is
> composed of two subnets. Subnet 1 has prefix 3ffe:b80:17d2:1 and subnet 2
> has prefix 3ffe:b80:17d2:2. Each subnet has a FreeBSD Router in its
> domain. The two FreeBSD routers are "IPv6" connected using gif tunnels
> using the existing IPv4 routing framework. The router in subnet 1 is
> connected to freenet6 (through another gif tunnel.
> 
> Router 1
> --------
> 
> gif0: flags=8251<UP,POINTOPOINT,RUNNING,ALLMULTI,MULTICAST> mtu 1280
>         inet6 fe80::260:8ff:fe11:d903%gif0  prefixlen 64
>         physical address inet 128.4.1.3 --> 128.4.2.16
> gif1: flags=8051<UP,POINTOPOINT,RUNNING,MULTICAST> mtu 1280
>         inet6 fe80::260:8ff:fe11:d903%gif1  prefixlen 64
>         inet6 3ffe:b80:3:197b::2 --> 3ffe:b80:3:197b::1  prefixlen 128
>         physical address inet 128.4.1.3 --> 206.123.31.114
> 
> 
> Router 2
> --------
> gif0: flags=8051<UP,POINTOPOINT,RUNNING,MULTICAST> mtu 1280
>         inet6 fe80::250:daff:fedd:5333%gif0  prefixlen 64
>         physical address inet 128.4.2.16 --> 128.4.1.3
> 
> Our requirement is to set up NTP multicast servers at our site (subnet1
> and subnet2). The NTP IPv6 site multicast address is ff05::101. An NTP
> packet sent to this address (or any address starting with ff05::) from any
> machine on subnet1 or subnet2 should be received by all machnies on both
> subnets. The router on subnet 1 should drop all ff05 packets received from
> freenet6 and should not route any ff05 poackets over to freenet6.
> 
> I would aprreciate any help in this regard...

I use pim6dd from ports and in /usr/local/etc/pim6dd.conf I have
phyint stf0 disable
phyint gif0 disable
phyint gif2 disable

A few other odds and ends. You will need "options MROUTING" in your
kernel. Multicasting also seems to work better if there is a specific
route for it in the kernel. I use this in my /etc/rc.conf file, adjust
fxp0 to what you have locally:

ipv6_static_routes="sitemcast"
ipv6_route_sitemcast="ff05:: -prefixlen 16 ::1 -ifp fxp0"

And yes I did all this just for ntp. :-)

John
-- 
John Hay -- John.Hay@icomtek.csir.co.za / jhay@FreeBSD.org