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Crossover GbE link between two computers

Last response: in Networking
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February 7, 2006 7:22:21 PM

Hi, new member here, and a bit of a newbie. Been trying to set up a direct Gb link between two computers connected to the same router and could use some advice.

Goal is to have all internet traffic going through the router, while communication between the two computers avoids the router/switch and uses the faster Gb link.

Currently have the GbE nics on both comps set to static on a unique subnet, while the links to the router are assigned static ips on the normal LAN subnet. This works fairly well, but can tell that occasionally the computers try to direct internet requests via each other. My question is, any simple way to configure static routes so that the traffic between the two computers always uses the GbE nics, and internet traffic always gets sent through the other cards? Hoping to buy a gb switch in the future, but attempting to get this setup to work before adding more computers.

Using Intel Pro 1000 MT Dual on one machine and onboard marvell chipset on the desktop for gb links.


Thanks in advance for any help!
B
February 7, 2006 8:10:52 PM

The easiest way is to block port 80 in MS firewall related with the port. It is under advanced options.
February 7, 2006 8:26:27 PM

Quote:
The easiest way is to block port 80 in MS firewall related with the port. It is under advanced options.


Hm, currently not using MS firewall on either comp (XP & 2k3), as sitting behing a hardware firewall. Blocking port 80 across the GB link would work..but was hoping for a more comprehensive solution, as other ports are in constant use for internet traffic.

Just found the following article on configuring static routes. Hoping that adding a persistent route on both machines will be a hacked together way to get this working.. Wanted to cheaply try out jumbo frames across the link. Any thoughts on this approach?
Related resources
February 7, 2006 8:52:23 PM

Having a look at the routing tables, Im thinking I'll have to add a high metric route to dest 0.0.0.0 across the GB link subnet, to dissuade internet traffic from being sent that way, while adding a low metric route for traffic w/ dest. within the GB subnet..

Obviously a bit out of my element here...

Lan Subnet is 192.168.x.x range
GB Subnet is 10.1.1.x range

Hm. Perhaps this isnt a great strategy w/ poor knowledge of iptables/routing. Any suggestions appreciated : )
February 8, 2006 1:02:26 AM

Found the following post on the same setup, but adding little.
February 10, 2006 6:57:16 PM

First off you need to disable IP forward on both of those machines so windows doesn't think you are runing a router. That will solve the problem of forward internet traffic through the other machine. Having those machines directly connected to each, that is always going to be the preferred route for direct communication.

Look at your routing table. If a route to the other machine is there, it's going to take that route because forwarding decision will be based on the longest bit mask match, i.e. 255.255.255.252 will be matched before 255.255.255.0.
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