Julian's netowrking challenge 2005

[Jeremie Le Hen]

Hi Julian,

> The challenge:
> 
> figure out a way so that all teh users on the network behind fxp0
> hcan use the internet using the T1 attached to the cisco off fxp1
> while all the advertised services (about 8 of them, few enough to
> list by hand in rules etc.) which are also behind fxp0 but acccessed by 
> NAT'd addresses from the addresses on fxp1's net are accessed soly via that 
> T1.
> 
> [...]
> 
> I can get the 'forward' direction easily.. i.e. incoming packets.
> 
> It's the reverse direction that doesn't work for me.
> I considerred running 2 NATDs
> but I need to run ipfw to identify teh reverse streams to force back via 
> fxp2
> and the only way I can do that is by using the 'fwd' command.
> if I do that I can't divert them and if I divert them to natd first, I can't
> 'fwd' them afterwards as the NATing is already done for the other (wrong)
> interface.

You definitely want a non-terminal "fwd" command.
Ari Suutari has just implemented the "setnexthop" action that does the
trick, I think the patch [1] is waiting to be commited in -CURRENT.
I don't think this would be really difficult to backport to RELENG_4.

Hope this helps.
Regards,

[1] http://lists.freebsd.org/pipermail/freebsd-net/2005-June/007710.html

PS: I'm seeing more and more requests about routing limitations in
FreeBSD everyday, such as lack of multiple routing tables support, lack
of source routing (as well as higher level protocol based routing).
Are there actually some projects that are being worked on to overcome
this ?
-- 
Jeremie Le Hen
< jeremie at le-hen dot org >< ttz at chchile dot org >