Re: [Cerowrt-users] 6in4 links

[Phil Pennock <cerowrt-users+phil@spodhuis.org>]

On 2012-12-10 at 09:47 +0100, Dave Taht wrote:
> On Mon, Dec 10, 2012 at 9:45 AM, Phil Pennock <phil.pennock@spodhuis.org> wrote:
> > On 2012-12-09 at 21:04 -0500, Michael Richardson wrote:
> >> The problem is that the interface that is created is a /128, and it's
> >> the ::2, but since it is a /128, the ::1 isn't "On-network", so the
> >> static route fails.
> >
> > Er, a /128 means there can be no route associated with it, this is used
> > typically for things like additional aliases on an interface.
> 
> Actually, we route p2p /128's via the babel protocol, and distribute
> /128s via the ahcp protocol. Works great.

I was imprecise.  Sure, with routing delegated by the kernel to a
routing daemon, you can do anything routing-wise, all bets are off.

I know you know this Dave; I'm not trying to teach you how to suck
rotten eggs, I'm clarifying my assertion.

For _static_ routes, per the OP, where you have link-layer addresses and
need to make a determination of what link-layer address should be
attached to a frame going out of an interface, a /128 does not convey
enough information.  Something needs to translate the routing
information from the user-space layer to something that can be used for
packets.  The route(8) command can not specify L2 recipient addresses.

On Linux, you can specify a peer's L2 address with ifconfig(8) or ip(8),
which can work in conjunction with a route, which might be enough for
the OP, depending upon exactly what is happening?

-Phil