Using Multiple Internet Connections with FreeBSD

[John Barbieri]

Thanks for the reply, but this isnt exactly what I was looking for.

This one is used to force packets out to a specific network depending on
the destination IP address and such.


I was looking for something that would allow for both rundunancy and
speed increase, similar to PPP multi-link or connection teaming (which,
from what ive read, can effecticly double bandwidth).

Thanks again

John

Philip Hallstrom wrote:

>> To start off, I have a FreeBSD router running Nat and dhcp, it is
>> currently the router for my LAN.
>>
>> I was wondering if there was a way to aggregate more then one internet
>> connection using FreeBSD?
>>
>> That is, have 2 or 3 internet connections coming in on seperate NICs,
>> and being able to have the box route and nat the packets accordingly to
>> the lan, thus giving the experience of more bandwidth. Is it even
>> possible?
>>
>> Has someone done it before? and if you have, do you have a webpage that
>> you followed instructions from?
>
>
> I haven't done it, but I've saved the following email/posts that
> talked about this...  I've left them intact so you can see the context...
>
> good luck!
>
>> From gerti at bitart.com Wed Dec 24 09:35:16 2003
>
> Date: Fri,  3 Nov 2000 18:46:34 -0600
> From: Gerd Knops <gerti at bitart.com>
> Reply-To: gerti-freebsdq at bitart.com
> To: Simon Nielsen <simon at dkik.dk>
> Cc: questions at FreeBSD.ORG
> Subject: Re: Two ISP's. Two IP. One default route...
>
> Simon Nielsen wrote:
>
>> Hello
>>
>> I currently have two internet connections though two different ISP's.
>> One is a ADSL and another is shared with the rest of my dorm. The
>> shared line is rather slow because many people are using it.
>>
>> I must have an IP on the shared connection since that's the only
>> place where I can be sure to have a non changing IP for my DNS. But
>> the ADSL is much faster so I would like to use that as much as
>> possible.
>>
>> I can give my machine an IP on each connection but I can of course
>> only set one default route. The default route is currently set to the
>> ADSL. The problem is that when a connection is made to IP on the
>> shared connection my computer uses the ADSL IP to respond and that
>> does not work.
>>
>> Is there a solution to this? I thought about maybe it is possible to
>> route differently when a connection is made on the shared connection
>> but I can't find out how to do it.
>>
> Yes, it can be done (though I have not found it documented anywhere).
> I really think there should be separate routing tables for each
> interface, but I don't know of any such feature in any Unix.
>
> However ipfw can be abused for the above task. Assuming:
>
>     - ipfw is set to pass on default
>     - your ADSL IP/network is a.a.a.a/aa
>     - your shared IP/network is s.s.s.s/ss
>     - your ADSL gateway is set as default route
>     - your shared gateway is s.s.s.gw
>
> the following ipfw rules do the trick:
>
> # Pass anything that should go via normal routes
> # This rule is really just to speed up the bulk
> # of the packets
> add 1000 allow all from a.a.a.a to any
> # Pass anything to local addresses on ADSL network
> add 1010 allow all from any to a.a.a.a/aa
> # Pass anything to local addesses on shared network
> add 1020 allow all from any to s.s.s.s/ss
> # And here the trick: if the source address is the one
> # from the shared network, pass packets to the
> # gateway on the shared network
> add 1030 fwd s.s.s.gw all from s.s.s.s to any
>
> With the above connections will leave your system on the same route
> they entered it. Great for redundant mail and dns setup!
>
> If you already use ipfw you need to adapt the above rules accordingly.
> The important part is that packets coming from your host's shared
> address going to the 'outside' (and only those packets) are forwarded
> to the shared networks gateway.
>
> Gerd
>
>
>> From mwm at mired.org Wed Dec 24 09:35:23 2003
>
> Date: Sat, 4 Nov 2000 09:34:48 -0600 (CST)
> From: Mike Meyer <mwm at mired.org>
> To: Simon Nielsen <simon at dkik.dk>
> Cc: questions at FreeBSD.ORG
> Subject: Re: Two ISP's. Two IP. One default route...
> Resent-Date: Wed, 24 Dec 2003 10:35:16 -0800 (PST)
> Resent-From: Philip Hallstrom <philip at alkinetworks.com>
> Resent-To: Philip Hallstrom <philip at eilio.com>
> Resent-Subject: Re: Two ISP's. Two IP. One default route...
>
> Simon Nielsen <simon at dkik.dk> types:
>
>> I currently have two internet connections though two different ISP's.
>> One is a ADSL and another is shared with the rest of my dorm. The shared
>> line is rather slow because many people are using it.
>>
>> I must have an IP on the shared connection since that's the only place
>> where I can be sure to have a non changing IP for my DNS. But the ADSL
>> is much faster so I would like to use that as much as possible.
>
>
> Question: what are you using the static IP for? I.e. - who connects to
> it, and vice versa?
>
>> I can give my machine an IP on each connection but I can of course only
>> set one default route. The default route is currently set to the ADSL.
>> The problem is that when a connection is made to IP on the shared
>> connection my computer uses the ADSL IP to respond and that does not
>> work.
>>
>> Is there a solution to this? I thought about maybe it is possible to
>> route differently when a connection is made on the shared connection but
>> I can't find out how to do it.
>
>
> Well, if you can narrow down who connect on the shared connection, you
> can add a route for those addresses pointing to the shared
> connection. It's been about five years, but I used to do that, but if
> the only people connecting to the shared IP are on the campus net, you
> can add a route that looks like
>
>     route add -net campus.net static.ip [campus.netmask]
>
>     <mike
>
>
> -------- Original Message --------
> Subject: two isps routing
> Date: Wed, 28 Jan 2004 16:38:52 -0800 (PST)
>
> http://www.tldp.org/HOWTO/Adv-Routing-HOWTO/lartc.rpdb.multiple-links.html
>
>
>
>