[CentOS] Configuring Multiple Gateways

Wed Nov 22 21:43:35 UTC 2006
Kevan Benson <kbenson at a-1networks.com>

On Wednesday 22 November 2006 13:27, Matthew Martz wrote:
> On Wed, November 22, 2006 1:42 pm, Matthew Martz wrote:
> > I'm in need of installing two NICs in a machine that are connected to 2
> > different public networks and I need both IP addresses accessible from
> > the outside.  The IPs are part of two completely different subnets.
> >
> > For example:
> > eth0
> >      IP - 10.10.10.2/30
> >      GW - 10.10.10.1
> >
> > eth1
> >      IP - 20.20.20.6/30
> >      GW - 20.20.20.5
> >
> > How can I configure 2 gateways on this server?
>
> I should probably also mention that I want traffic that comes in over eth0
> to go out over eth0 and traffic that comes in on eth1 to go out on eth1.

I'm not a networking guru, and this isn't really my domain, but it sounds like 
maybe you should use some sort of routing daemon to control this with more 
features than route(8) allows.

The quagga package (in the base package set) is a fork of zebra, and I think 
it will do this and more if you need.  If this is overkill or just plain 
incorrect, maybe some people that know better will be tempted to post to 
correct me...

P.S.
There are howto's on getting link load sharing using routes and iptables rules 
that may implement this bahavior as a side effect.  Googling for that may 
yield some good information as well.

-- 
- Kevan Benson
- A-1 Networks