Computer Router Problems

[Xairen]

Good morning everyone (afternoon / evening to some)!

I have a very basic understanding of computer networking, meaning I know which cable goes where so I can follow instructions easily 😛

I am having problems setting up a relative's internet connection in their small family business (which they desperately need to work for them to make $$$).

Here's the setup that I want to achieve:

Modem (Telus Actiontec V1000H) - With 2 Routers connected to it.

• 
  Router 1 (D-Link WBR-1310) - With 4 Items connected to it via LAN cables.
  • 
    Computer 1
    Point-of-Sale Unit 1
    Point-of Sale Unit 2
    Printer 1
  Router 2 (D-Link DES-1005E) - With 3 Items connected to it via LAN cables.
  • 
    Computer 2
    Point-of-Sale Unit 3
    Printer 2

What's happening is, when I do this setup, the computers lose INTERNET connection but are connected to a local network, the other items (printers and POS units) have working internet connection.

Now, when I remove the computers from the routers and connect them directly to the modem, they regain internet connection IF Router 1 is disconnected. If I do this, POS Unit 2 can't be used because the modem does not have enough ports.

This is driving me nuts. With my understanding, as long as the 2 routers are connected to the modem, all the units connected in each router should have a working internet connection.

What do I do with this?

 

[boosted1g]

You have a few problems going on here.

First off by having 2 routers you have 2 separate networks, thus computer 1 cant communicate with any devices on router 2. Routers have what is called NAT (Network Address Translation), this means that all of the devices bellow the router have a different address scheme then the IP address coming into the router. This is the first essential building block to having any type of security, without this it would be as pointless as building the most secure gate in the world but no fence so you can just drive around it.
If there is no wireless devices, then instead of the second router you just need a basic Ethernet switch.
If there is wireless devices on router 2 then you need to buy a dedicated access point or just configure router 2 to be an access point.


The other problem you may be running in to is that you are hooking 2 devices directly into the modem. If the modem is a modem only (vs a modem/router combo device) then the modem can not issue new IP addresses, it only has the address(es) provided via the ISP so if you are not specifically paying for 2 addresses then the modem will only allow the 1st router plugged into it to work.

This is what you currently have:
Modem -> Router 1 | Router 2 -> Devices

Here is what you need:
Modem -> Router 1 - > Devices, Ethernet switch/access point -> Devices
So you need to have Router 2 (whether it gets converted to access point or replaced with an Ethernet switch) plugged into router 1 and not the modem.

 

[Xairen]

You have a few problems going on here.

First off by having 2 routers you have 2 separate networks, thus computer 1 cant communicate with any devices on router 2. Routers have what is called NAT (Network Address Translation), this means that all of the devices bellow the router have a different address scheme then the IP address coming into the router. This is the first essential building block to having any type of security, without this it would be as pointless as building the most secure gate in the world but no fence so you can just drive around it.
If there is no wireless devices, then instead of the second router you just need a basic Ethernet switch.
If there is wireless devices on router 2 then you need to buy a dedicated access point or just configure router 2 to be an access point.


The other problem you may be running in to is that you are hooking 2 devices directly into the modem. If the modem is a modem only (vs a modem/router combo device) then the modem can not issue new IP addresses, it only has the address(es) provided via the ISP so if you are not specifically paying for 2 addresses then the modem will only allow the 1st router plugged into it to work.

This is what you currently have:
Modem -> Router 1 | Router 2 -> Devices

Here is what you need:
Modem -> Router 1 - > Devices, Ethernet switch/access point -> Devices
So you need to have Router 2 (whether it gets converted to access point or replaced with an Ethernet switch) plugged into router 1 and not the modem.

I see, I understood what you said but to clarify a few things:

1. The modem is a modem & router combo.
2. No Wireless devices are connected to either routers.
3. The network was okay yesterday when they closed the shop. This morning, the computers lost internet once they were booted up.
4. They restarted the modem while I was posting this message and it seems to have fixed the issue "for now".

Now that you mentioned it, I remember setting up my home network the same as your proposed solution. I'll set it up that way as well for them.

Thanks a bunch!

 

[boosted1g]

Glad you got it working, so you in fact have triple NAT going on.

This is going to be a complete nightmare if they will ever need to access something in the office from the internet as you would need to port forward on potentially 3 different routers. Not to mention you cant just configure routers (including the router/modem) from any PC, you would have to plug that pc directly into the device you want to configure.


Most modem/routers allow you to configure them to be in "bridge mode" or "modem only mode" so they wont act as a router anymore (which also means no wireless from it).
I would set your modem to that, then plug router 1 into modem, and then of course plug router 2 (or switch) into router 1.
As I stated earlier, if you don't need wifi from router 2 just replace it with an inexpensive gigabit switch (you can get a 8 port for $20 or less); otherwise you can configure an router to be access point.

Once you do all this you will have 1 large network and all PCs can communicate with each other and you can network printers and do file shares across the entire network and anything else networking related to help the business run more smoothly.