Policy Routing natd+ipfw

[Jason Hills]

On 5/5/07, Patrick Tracanelli <eksffa at freebsdbrasil.com.br> wrote:
> > How can I do policy routing with ipfw+natd?
> >
> > I started 2 natd processes, using natd.conf and natd2.conf
> > respectively, but things dont work. My rules are:
>
> Long time ago, PHK added an (undocumented, except for commit logs) feature
> in natd(8), called "instances". To use it, you can start a config file
> with the "instance" keyword followed with an identifier, and in a certain
> moment use the "instance" keyword again, with a second identifier. Each
> block will create different natd instances which can be used with
> independent configurations. However they are run by the same proccess.
>
> Here is an (production) example:

Very good, it worked fine. I am happy I can stop running 2 natds. It was ugly.

>
> To do so in your enviroment, divert packets to the second link when they
> reach the main outgoing interface (tradditional path the packet would
> flow, according to routing table):
>
> divert 8669 ip from $net2 to any out via $ext_if1
>
> Yes, this WILL work. Packets will be diverted to second natd instance when
> it reaches the main outgoing interface (as main, I want you to read: the
> one used by default route).

It sounds like it worked. Packets hit the rule correctly, but I dont
go to Internet.

>
> So, here you are forgetting another mandatory flow control: you have to
> send packets from your second-link IP address to your second-link gateway.
> IPFW´s "fwd" action will do this like a charm =)

I believe this is why I dont get to internet. I didnt understand this
ipfw fwd thing you mentioned. Could you give some example?

>
> >
> > divert 8668 ip from any to any via $ext_if1
> > divert 8669 ip from any to any via $ext_if2
> >
> > My defaultrouter is the one on $ext_if1.
> >
> > It works for port 8668 but doesnt work for 8669 (the second xDSL link)
> >
> > --
> > Jazzie Hills
>
>
> --
> Patrick Tracanelli
> (31) 3281 9633
> sip://313306@sip.freebsdbrasil.com.br
>
>


-- 
Jazzie Hills