One linux box and nic card, two high-speed internet connections

ajnunes · 10-01-2002, 12:38 AM

I have a linux box (Red Hat) connected to a switch (one nic card only). To that same switch, I have a Win xp machine that serves as the gateway for a DSL internal modem, and a router that servers as the gateway to an external wireless modem.

By changing the gateway in ifcfg-eth0, I can get trafiic to flow through either DSL or wireless, but not both. For example, if I use the DSL gateway, then traffic coming through the wireless gets lost. It acts as if requests coming from the wireless are answered through the dsl.

How can I make this work so the network sends the answers through the gateways that asked the questions?

Thanks
TJ

penseur2 · 10-01-2002, 09:26 PM

hi,

i'm guessing you want to switch to linux for the routing . go to tldp.org. in the howto's section you will find a 2.4 advanced routing howto. see the section on split access and load balancing over multiple providers.
you setup will be linux as the primary gateway connected to both your dsl modem and your wireless modem.
before starting check whether the wireless modem is linux compatible. the dsl should'nt be a problem.

regards
penseur2

adam_boz · 10-03-2002, 01:43 AM

Something sounds wrong with your topology. basically, your network IS the switch, and you have two ways to get out? you need to have only one point of entry for the network. it would work if your switch was a router (and a nifty one at that), then it could utilize both isp connections to get really high bandwidth for your internet connection.

I don't know... maybe i am reading it worng

ajnunes · 10-24-2002, 04:34 PM

I finally got around to reading the document that penseur2 told me about, and I got it working! Thanks!

To answer adam_boz question/concern, it's not the switch that matters, is the IPs associated with each of the two NICs that I have in my Linux box. I had to insure that those ips were in two distinct networks, i.e., that the 3 first bytes of each ip were different. In my case, 192.168.0.x and 10.10.10.x. Then, I had to insure that the internal IP for the 192.168.0.x gateway (a windows box) was in that same range, and that the internal IP for the 10.10.10.x gateway (a router for a wireless modem) was also in this other ip range. This provides two distinct networks, even though all cables are connected to the same switch.

After that, it was a piece of cake to implement the routing tables and rules.

Thanks a bunch.
TJ