Single Computer - Two Wired Networks

[aphex]

Need some help here as I'm a bit confused as to what the issue is and how to resolve it. I'm helping a friend set up some new computers at his new gas station, and one in particular has been giving us some trouble.

One side of the network is a system called Nucleus that the POS (Gas Pumps/Register run on). The Nucleus is set at 192.168.1.1 and connected to a Gateway (which all the pumps are connected to). The gateway in turn is connected to the FIOS Router/Modem and the techs are able to dial in just fine to each of the pumps.

The other side of the network is the normal LAN for the other PC's. They are plugged into the FIOS router/modem directly for Internet Access, but have no connectivity to Nucleus.

The computer we need help with is running Windows XP, dual ethernet ports (one onboard, the second a PCI card). The PC is connected directly to Nucleus with a static IP. The PC can see Nucleus, ping Nucleus and Map a Drive as needed.

The problem arises when I connect the PC to the FIOS Router/Modem with the second ethernet card. We immediately get internet access on the PC, but then all pings to Nucleus (192.168.1.1) start to time out and are unable to connect. We checked for IP conflicts but there appear to be none, so were kinda confused what the issue is.

Here are the settings;

PC
Ethernet 1 - Direct Connection to Nucleus (at 192.168.1.1), Static IP - 192.168.1.10
Ethernet 2 - Connection to Router/Modem (at 192.168.1.7), Auto DHCP - 192.168.1.21

Nucleus
Static IP - 192.168.1.1

FIOS Modem/Router
Static IP - 192.168.1.7
DHCP Range - 192.168.1.21-50

Any ideas how to get the PC to recognize both networks at once? All we really need is for this computer to have full internet access (with the connection to the FIOS Modem/Router) as well as be able to have a direct connection to Nucleus (at 192.168.1.1 on the other ethernet)

 

[xSauronx]

Originally posted by: aphex

PC
Ethernet 1 - Direct Connection to Nucleus (at 192.168.1.1), Static IP - 192.168.1.10
Ethernet 2 - Connection to Router/Modem (at 192.168.1.7), Auto DHCP - 192.168.1.21

Nucleus
Static IP - 192.168.1.1

FIOS Modem/Router
Static IP - 192.168.1.7
DHCP Range - 192.168.1.21-50

Any ideas how to get the PC to recognize both networks at once? All we really need is for this computer to have full internet access (with the connection to the FIOS Modem/Router) as well as be able to have a direct connection to Nucleus (at 192.168.1.1 on the other ethernet)

the issues is that the PC has two NICs that are both on the same network (192.168.1.*) this cant be done.

it sounds like Nucleus has two interfaces: one connected to the PC, and one connected to the gateway. is that right? you only listed one IP for it though.

either way, you really need 2 subnets in your network if that gateway is going to remain a gateway. you need one subnet for your modem/router, and one subnet for everything else behind the gateway.

as long as you use just one, both connections on that PC wont work, and I wouldnt be surprised if you had problems at some point with the Nucleus as well.

at the very least the connection between the PC and the Nucleus needs to be on a different subnet.

 

[aphex]

Originally posted by: xSauronx

Originally posted by: aphex

PC
Ethernet 1 - Direct Connection to Nucleus (at 192.168.1.1), Static IP - 192.168.1.10
Ethernet 2 - Connection to Router/Modem (at 192.168.1.7), Auto DHCP - 192.168.1.21

Nucleus
Static IP - 192.168.1.1

FIOS Modem/Router
Static IP - 192.168.1.7
DHCP Range - 192.168.1.21-50

Any ideas how to get the PC to recognize both networks at once? All we really need is for this computer to have full internet access (with the connection to the FIOS Modem/Router) as well as be able to have a direct connection to Nucleus (at 192.168.1.1 on the other ethernet)

the issues is that the PC has two NICs that are both on the same network (192.168.1.*) this cant be done.

it sounds like Nucleus has two interfaces: one connected to the PC, and one connected to the gateway. is that right? you only listed one IP for it though.

either way, you really need 2 subnets in your network if that gateway is going to remain a gateway. you need one subnet for your modem/router, and one subnet for everything else behind the gateway.

as long as you use just one, both connections on that PC wont work, and I wouldnt be surprised if you had problems at some point with the Nucleus as well.

at the very least the connection between the PC and the Nucleus needs to be on a different subnet.

Ahhhh, ok. That makes sense. However, from this point I'm kinda limited in what I can do as I can't modify anything in regards to Nucleus and the Gateway they use, nor can I change the IP of the FIOS Router (They have a company who comes in and sets up Nucleus, but won't touch the local network for anything else).

Would it work if I simply made the connection between the PC and Nucleus in a different subnet? (Change the IP of the PC to 192.168.2.10 for that connection?)

 

[JackMDS]

The system has to be split to two Networks with two different subnets.

Example, 192.168.111.1 and 192.168.222.1

The computer with the two NICs has to Run WinXP Pro or Vista and the two NICs has to be Bridged.

See the principle on this page, http://www.windowsnetworking.c...utorials/wxpbrdge.html

 

[Cooky]

Originally posted by: JackMDS
The system has to be split to two Networks with two different subnets.

Example, 192.168.111.1 and 192.168.222.1

The computer with the two NICs has to Run WinXP Pro or Vista and the two NICs has to be Bridged.

See the principle on this page, http://www.windowsnetworking.c...utorials/wxpbrdge.html

Without bridging two NIC's, you can also assign default gateway to only one NIC.

 

[aphex]

Thanks guys!

So if I go into the router, change the DHCP server to 192.168.2.1-20 and bridge the two ethernet connections on the PC, we should be in business? Also, is it ok if the router's IP is outside the subnet? (The router will be 192.168.1.7 while the DHCP will be assigning addresses 192.168.2.1-20)

 

[VirtualLarry]

Most routers will only assign DHCP addresses on the same subnet that their LAN address is on. So no, you can't have the router's LAN IP of 192.168.1.7, and have it hand out 192.168.2.1 IPs. However, if your router's WAN IP is 192.168.1.7, and it's LAN IP is 192.168.1.1, then it will work.

 

[aphex]

Originally posted by: VirtualLarry
Most routers will only assign DHCP addresses on the same subnet that their LAN address is on. So no, you can't have the router's LAN IP of 192.168.1.7, and have it hand out 192.168.2.1 IPs. However, if your router's WAN IP is 192.168.1.7, and it's LAN IP is 192.168.1.1, then it will work.

Damn. Well, I don't have any access to adjust anything on Nucleus, so any changes I make have to be on the one side only (I can't adjust the IP of the router either as the Nucleus is set to look for its IP)

So, if what you say is true, that I can't set the DHCP outside the same subnet as the IP of the Router, would introducing a second gateway/router on the one side that I can work on fix the issue?

 

[kevnich2]

change the IP of the FIOS Modem/Router to 192.168.2.1. If the nucleas is connected to the gateway, it doesn't even see the FIOS modem, the gateway sees that. Is the gateway set to static IP or dynamic? If dynamic, by changing the FIOS modem to 192.168.2.1, the gateway will just get a new IP of 192.168.2.x on one side and the LAN side where the nucleas is connected will stay the same. Until you get the two sides to be on two different subnets, things won't work correctly at all. A computer with 2 NIC's cannot have both of them on the same subnet, it doesn't know where to send the traffic to.

You could also change the FIOS modem to 192.168.2.1 (or anything other than 192.168.1.x) and then attach another router to it that is then connected to the gateway and the nucleas and assign the second router as 192.168.1.7 on it's LAN side (WAN set to dynamic).

 

[aphex]

Originally posted by: kevnich2
change the IP of the FIOS Modem/Router to 192.168.2.1. If the nucleas is connected to the gateway, it doesn't even see the FIOS modem, the gateway sees that. Is the gateway set to static IP or dynamic? If dynamic, by changing the FIOS modem to 192.168.2.1, the gateway will just get a new IP of 192.168.2.x on one side and the LAN side where the nucleas is connected will stay the same. Until you get the two sides to be on two different subnets, things won't work correctly at all. A computer with 2 NIC's cannot have both of them on the same subnet, it doesn't know where to send the traffic to.

You could also change the FIOS modem to 192.168.2.1 (or anything other than 192.168.1.x) and then attach another router to it that is then connected to the gateway and the nucleas and assign the second router as 192.168.1.7 on it's LAN side (WAN set to dynamic).

I'm not sure how the Nucleus/Gateway is set up, but its set to look for the static LAN IP for the FIOS, so if I change the IP address of the router, their whole end stops working until they go in locally and change it to the new IP. I tried that the other day. Unfortunately from this point on, having them come back to change it isn't really an option, so I need to figure out what I can do without changing the LAN IP of the FIOS.

Forgetting the DHCP server for a second, what if I just put the PC into its own subnet for its connection to the router? Just bind it to a static IP in the 192.168.2.x range, and do the same for any subsequent PC's that are on that side of the router.

 

[aphex]

Well i'm gonna give it a shot in the AM, i'll let you know how it goes.

 

[imagoon]

While I am not sure, it sounds like your nucleus device and the FIOS networks are the same network. If that is the case, you will not need 2 cables. In order for the nucleus device to hit the FIOS router is would need to be on the same network. So you should be able to just configure the static IP on the computer with the DNS / Gateway information that DHCP would normally give you automatically and the PC would be able to access the net through the FIOS line.

 

[aphex]

IT WORKED!!! I used an old Dlink router, set the WAN IP in the subnet of the main FIOS router, set the gateway and DNS to the FIOS as well, turned off DHCP and used a static IP on the PC for the second subnet (192.168.2.101). The PC can now see the Nucleus at 192.168.1.1 just fine as well as access the internet. THANKS!!!!

Now, one question, the PC is unable to access the FIOS router's configuration page (at 192.168.1.7), but another PC on the same subnet (192.168.2.102) can just fine. Any idea why? Is it looking at Nucleus to provide the data from that subnet rather than its net connection through the Dlink?

 

[aphex]

Also, how would I go about port forwarding through the two routers?

Lets say I need port 6149 forwarded, do I do this?

FIOS forwards 6149 to 192.168.1.20 (WAN IP of the DLink Router)
DLink forwards 6149 to 192.168.2.101 (IP of computer)

?

EDIT: Yep, that worked!!