Re: Seeking info on multiple, simultaneous Net connections

[hartr interweft com au]

On  2 Dec, Steve Snyder wrote:
> I've just gotten a second Internet connection on a machine that is used as 
> a LAN gateway to the Internet.  So now this box (Redhat v7.2 /w 2.4.16 
> kernel) has: 
> 
>   eth0 - internal LAN
>   eth1 - ISP #1 (ISP1)
>   eth2 - ISP #2 (ISP2)
>   
> I've had ISP1 all along and would like to keep it as my primary connection 
> to the Internet (it's the faster of the 2 connections).  My first choice 
> for ISP2 would be for concurrent use with ISP1, i.e.  to augment ISP1's 
> bandwidth.  My second choice would be to use it as a fallback interface 
> should ISP1 be offline.  
> 
> I currently use iptables to masquerade LAN traffic and to act as a firewall 
> on the ISP1 interface.
> 
> These preferences leave me with a lot learning to do:
> 
>   1. How to integrate a 2nd external connection into my firewall config?

The simplest way is to specify the firewall rules for each interface.

>   2. How to use 2 Internet connections (different ISPs) concurrently?

You can only have a single default route, but you can add specific
routes to specific addresses/networks via the other interface.

>   3. Interface fallover:
>     a. Config box such that ISP1 failure is detected and ISP2 takes over.
>     b. Config box such the restoration of ISP1 connectivity is 
>        re-established and making it again the primary gateway.

Write a script that watches the interfaces and swithces between them
accordingly.

>   4.  How to direct certain IP addresses to a specific interface (mail
>        destined to a specific ISP's mailserver goes to that interface.)

Use the route command to add the specific routes - see above.

It might be simpler to learn how to setup gated (it's part of the 7.2
distro as this will do what you want to do...

        
> I've looked over the HOW-TO on the Linux Documentation web page and don't 
> see these topics addressed.  Can someone point me to resources that 
> describe the handling of multiple sources/destinations of Internet traffic? 
>  
> 
> Thanks.
> 
> 
> 
> _______________________________________________
> enigma-list mailing list
> enigma-list redhat com
> https://listman.redhat.com/mailman/listinfo/enigma-list

-- 
Robert Hart					 hartr interweft com au
Strategic IT & open source consulting                +61 (0)438 385 533
Brisbane, Australia			    http://www.interweft.com.au