2 Internet connections, 3 PC's, 4 NICs & 2 routers

[mysticman]

The Situation:

Three home-workers - my girlfriend & I plus her (female) cousin in the apartment next door. We started out a few months ago with one a DSL connection (cousin's) and a Linksys WRT54G router (mine) but disabled the wireless (temporarily hopefully) and networked the three Windows XP PC's together via the router and a switch - router in cousin's apartment & switch in ours so only 1 cable comes across from cousin's apt.

We use the internet extensively for research and for communicating with clients and we work collaboratively on all our projects so we also share files extensively amongst ourselves.

Things have gone surprisingly well in the few months of operation (we actually get to eat daily now) but we are putting our single DSL connection under strain because of large file transfers to/from clients. Today we got another DSL connection hooked up by a different supplier and bought another WRT54G router and a second NIC for my computer. We have agreed that I should have the full bandwidth of the new connection while the two ladies will share the original line. Now we three marketing consultants and network manager wannabe's have realised that we have no idea how to connect our 3 PC's to a network with 2 internet connections.

The Plea for Help:

We would all be truly grateful if a real network person can tell us how to connect 3 PC's, 2 routers, one switch, 4 NICs and 2 DSL connections so that one computer has the full bandwidth of one DSL and we can all share files seamlessly

 

[Ethereal_Dragon]

Wouldn't it have been easier (and possibly cheaper) to upgrade the existing DSL connection, than get an additional one?

Anyways... you say that there are 3 computers, but 4 NIC's?? If you have 2 NIC's in your PC, you could hook up your computer to the one DSL connection, and the 2 other computers to the switch, and the switch to the other DSL connection... You could then connect your PC to the switch via the 2nd NIC. Just make sure that the 2nd NIC is in a different subnet than the first, and that it is in the SAME subnet as the other 2 PC's... In thoery, I suppose that should work, but real-world, not too sure. It will be interesting. If you can, block your computer's 2nd NIC address from internet access through that modem.

 

[jmhill1976]

It's actually not that difficult to accomplish what you are attempting to do, and it sounds as if you have all of the components necessary.

On your old NIC, you should assign a manual address IP address, but do NOT include a default gateway or DNS servers. I'm assuming your current router uses DHCP, so you'll have to select an address which is reserved ... actually you can simply choose one which is higher than those currently active on the network, as I assume you aren't going to have more than 9 or 10 devices on your network.

To see what addresses you can use, go to one of the other computers, go to a command prompt, and type 'ipconfig.' Look at the line that says IP address, and just choose a number that is ... say, 20 digits higher than the last octect (192.168.0.this number). You'll also want to take down the subnet mask, although it is probably 255.255.255.0. Ignore the setting for default gateway, you'll want to leave this blank.

On your PC which you are connecting to the new DSL router, do NOT install the 2nd NIC yet. You should now go to the command prompt and type the following:

ipconfig /release

This will clear the automatic TCP/IP configuration on the NIC which is currently installed. At this point you will want to configure TCP/IP to use a manual address, which you will have extracted in the steps above.

Now, just for good measure, you should clear all of the route entries. Sometimes Windows hangs on to them, and it will only confuse things when trying to connect to the internet. Go to the command prompt again, and type:

route -f

Now install your second NIC, install TCP/IP and have it obtain an address automatically, and you should be good to go.

 

[jmhill1976]

Wouldn't it have been easier (and possibly cheaper) to upgrade the existing DSL connection, than get an additional one?

Anyways... you say that there are 3 computers, but 4 NIC's?? If you have 2 NIC's in your PC, you could hook up your computer to the one DSL connection, and the 2 other computers to the switch, and the switch to the other DSL connection... You could then connect your PC to the switch via the 2nd NIC. Just make sure that the 2nd NIC is in a different subnet than the first, and that it is in the SAME subnet as the other 2 PC's... In thoery, I suppose that should work, but real-world, not too sure. It will be interesting. If you can, block your computer's 2nd NIC address from internet access through that modem.

This won't work because his routers are most likely going to use DHCP, so they are both going to try to assign him a default route. He won't be able to get out to the internet because his routing table will get screwed up. Windows is stupid in that it allows DHCP to set a default gateways and overwrite a static route. This should NEVER happen, as the lowest metric should be assigned to statically assigned routes, and maybe it does actually assign a lower metric, but it doesn't take it into consideration when there are two NIC's with values for their default gateway.

Just configure one NIC manually with no default gateway and no DNS information, and allow the other to obtain it's information via DHCP from the "new" router.