configuring two outgoing gateways

[Erik Reuter <ereuter@erikreuter.com>]

I have two DSL lines which each have a different gateway and use a
different static IP address. I have both lines multiplexed onto the same
wire using a switch and cross-over cables, but I only connect to one DSL
line at a time on the ethernet card in my Debian box. Sometimes one of
the DSL lines will go down and I want to switch to the other one, so I
just swap in a different /etc/network/interfaces file:

cp /etc/network/interfaces.dsl2 /etc/network/interfaces 
ifdown eth0
ifup eth0

It seems to me there must be a better way to utilize the two DSL
lines. But I'm not sure where to start looking.

The ultimate would be to utilize the bandwidth of both lines
simultaneously to simulate one bigger bandwidth line, but I imagine this
will be difficult to set up.

The next best thing would be to have outgoing packets try the first
gateway, and if that fails, automatically try the second gateway. But
I'm not sure how to even begin to configure this.

I'd appreciate any suggestions on where I should start reading?



-- 
"Erik Reuter" <ereuter@erikreuter.net>       http://www.erikreuter.com/