Re: IPv6 nexthop for IPv4

On Thu, Mar 26, 2015 at 04:10:21PM +0100, Bjørnar Ness wrote:

2015-03-26 15:53 GMT+01:00 Sowmini Varadhan [off-list ref]:

quoted

On Thu, Mar 26, 2015 at 10:39 AM, Bjørnar Ness [off-list ref] wrote:

quoted

quoted

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ip route add 10.0.0.0/16 via fe80::225:90ff:fed3:bfb4/64 dev sfp0

Trying to understand what the desired behavior is, for the route
above: if I send a packet from 10.0.0.1 to 10.0.0.2, you want the dst-mac
to be the mac address of e80::225:90ff:fed3:bfb4???

Absolutely, correct.

What if the current node does not want to support ipv6? This sounds
pretty "creative", if this can work, you might as well make the nexthop to
be the L2 address of the gw.

If it does not support IPv6 I guess the route command will fail! This
is a bad argument
against this. Dont see the point of limiting nexthop to L2

This topic was discussed at the recent Netconf event in Ottawa.
This is a viable means of interconnecting two IPv4 "island" subnets
across an IPv6 "ocean" backplane.

Andy Gospodarek gave a short discussion on the topic, and IIRC it
was warmly received.  I'll Cc him on this message -- I think he had a
(fairly simple) patch more or less ready.

Hth!

John
-- 
John W. Linville		Someday the world will need a hero, and you
linville@tuxdriver.com			might be all we have.  Be ready.