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Old 07-17-2004, 12:29 AM   #16
Registered: Jul 2004
Location: New Orleans
Posts: 35

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Get rid of one of the routers. The windows box and linux box can run on the same ip scheme. I have it at home. I have 4 windows boxes, 1 ibook, and one linux box all on a Linksys Cable/DSL router with a Linksys Cable/DSL modem providing internet. You are not supposed to have two routers on one network. You can turn DHCP off on one of the routers and use it as a pass through.....Such as....Connect the DLINK via Crossover from lan port to lan port on netgear router....Disable DHCP on DLINK router and Voila....You should do this if you do not have enough ports on one router to supply connections to all your computers....Otherwise, remove a router and use only one router per ISP connection and do not join them together. You will get conflicts with packet info.
Old 07-21-2004, 11:33 AM   #17
Registered: Jul 2003
Location: Texas
Distribution: Mandrake
Posts: 65

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Well temdesign, you are wrong to a point.. You can have as many routers as you like on a network. I have had as many as 4 routers on one network. Routing ISDN, DSL and internal LAN. They all can talk using RIP, and distribute their routes among each other. He has to have more than 1 router because he running two dissimiliar internet access protocols. Cable AND DSL. You cannot operate both on the same "out of the box" gateway/ router. Now using 1 Linux box and 3 NICs I could make it all work using routing tables. The way you describing, it *might* work. In order to utilize both connections, you would have to configure each client with the gateway you want to use, doing so, I think that would eliminate the ability for DHCP, and you would have to use static IP addresses. I think that the way it is currently being done offers more security with network segregation.

try this:
route add -net netmask gw eth0
route add -net netmask gw eth1

This *should* if I remember correctly, route all traffic on the Linux through eth0, and route all traffic thru eth1

That might work, if not, restarting the network or a reboot will clear these routes. Tell if this doesn't work, we'll try another one.

Last edited by member57; 07-21-2004 at 12:12 PM.
Old 08-03-2004, 12:37 PM   #18
Registered: Feb 2003
Location: Toronto
Distribution: RH8 / FC1 / Gentoo / Debian / FreeBSD / Centos / Ubuntu
Posts: 182

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temdesign, I'm not understanding fully what you are saying. Anyways, where I've typed "windoze boxes" actually it's a mix of windows and linux boxes -- works fine -- no problem with that. The key thing is I am connected to both DSL and cable (2 different ISPs), so getting rid of a router is not an option (unless I tried member57's 3 nic idea, which does sound interesting). There are no conflicts - this setup works. However, I am unable to route traffic in through the cable modem directly to (due to no gateway on -- see previous post -- I'm able to specify eth1 and eth0 gateways, but only one can be active at a time, it seems). So instead, I am coming in via cable into another linux box on the LAN (one of the so-called "windoze boxes") with an SSH tunnel that redirects traffic to That way works, but I don't like being dependend on that 2nd linux box because I often use it for very cpu intensive stuff (like video rendering, for example). I want to be able to come directly into the server from the cable connection.

member57, I will give your suggestion a try soon. One concern: the server is an email server -- how is it going to know to use eth1 or eth0 for outgoing mail on port 25? I suppose the same question could be asked of any other outbound traffic from the server (browsing, ssh, etc, etc) -- which gateway will get used? Can the gateway be specified by port? app? something else? Or do I just need to accept the fact that there can only be one gateway on the server box?

Old 08-03-2004, 03:07 PM   #19
Registered: Aug 2004
Location: Europe
Posts: 608

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I think your problem can only be solved using a, kind-of heavy, advanced routing.
Have a glance at (and maybe all the previous chapters in the linux advanced routing and traffic control howto).
Old 08-03-2004, 09:12 PM   #20
Registered: Aug 2004
Distribution: Mandrake 10, Gentoo, and FreeBSD
Posts: 61

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