Load Balancing with Multi-path Routes

Greetings,

I'm trying to set up some sort of load-balancing on a Linux (Trustix)
gateway by using multipath routes, however I'm stuck with some problems.

The idea is that this gateway (odd as it may seem) only has one external
interface, which should route packets to two different gateways (Ciscos).
The gateway's external interface and the routers are all on the same
network, so this is a slightly different set up than the one described
in Linux Adv Routing HOWTO.

I successfully defined the multipath route, with two equal cost routes.
However, it doesnt matter how much traffic I generate on the gateway
(using many simultaneous wgets in mirror mode), it doesnt seem to distribute
the load among the two gateways, always using only one of them. I tried
both using and not using equalize, with the same result. I was carefull
to flush the route cache between each attempt.

Has anyone tried a similar setup (single interface + two gateways)? Is
this the proper way of doing such set up? Considering both routers are
on the same network of the gateway's external ínterface (and I cannot
change that), would there be any other alternative? Would I absolutely
need Julian Anastasov's patches for that matter?

Here's how my routing table looks like (IPs changed to protect the innocent):

js@virtual ~$ ip route show
198.X.Y.0/24 dev eth0 proto kernel scope link src 198.X.Y.1
127.0.0.0/8 dev lo scope link
default
nexthop via 198.X.Y.2 dev eth0 weight 1
nexthop via 198.X.Y.3 dev eth0 weight 1
js@virtual ~$

Any help would be greatly appreciated!

Regards,
John Sinclair

iptables can do load balancing!

nils

John Sinclair wrote:

> Greetings,
>
> I'm trying to set up some sort of load-balancing on a Linux (Trustix)
> gateway by using multipath routes, however I'm stuck with some problems.
>
> The idea is that this gateway (odd as it may seem) only has one external
> interface, which should route packets to two different gateways (Ciscos).
> The gateway's external interface and the routers are all on the same
> network, so this is a slightly different set up than the one described
> in Linux Adv Routing HOWTO.
>
> I successfully defined the multipath route, with two equal cost routes.
> However, it doesnt matter how much traffic I generate on the gateway
> (using many simultaneous wgets in mirror mode), it doesnt seem to distribute
> the load among the two gateways, always using only one of them. I tried
> both using and not using equalize, with the same result. I was carefull
> to flush the route cache between each attempt.
>
> Has anyone tried a similar setup (single interface + two gateways)? Is
> this the proper way of doing such set up? Considering both routers are
> on the same network of the gateway's external ínterface (and I cannot
> change that), would there be any other alternative? Would I absolutely
> need Julian Anastasov's patches for that matter?
>
> Here's how my routing table looks like (IPs changed to protect the innocent):
>
> js@virtual ~$ ip route show
> 198.X.Y.0/24 dev eth0 proto kernel scope link src 198.X.Y.1
> 127.0.0.0/8 dev lo scope link
> default
> nexthop via 198.X.Y.2 dev eth0 weight 1
> nexthop via 198.X.Y.3 dev eth0 weight 1
> js@virtual ~$
>
> Any help would be greatly appreciated!
>
> Regards,
> John Sinclair
>