Router and DSL Modem Issues

I spent most of last evening replacing my DSL modem with a new one.

This should have been a simple thing. My router is a separate bit of equipment, and had all the configuration stuff set up. I just got a simple modem, with a single ethernet jack. It looked very similar to the one that had bricked that morning.

Except it had a router in it as well.

Why you’d have a router in a bit of equipment with only one ethernet jack (and no wireless) I don’t know. Still, I got it to directly connect to my ISP and to my laptop. Next was getting it to share the connection through the wireless router.

So I spent the next several hours – including one and a half on the phone with tech support – trying to make the wireless router and the router in the DSL modem play nice with each other.

I tried turning DHCP off on one bit of hardware, then the other. I tried plugging cables into different ports. I don’t know how many times I reset and rebooted systems. I was almost able to get it to work by turning the wireless router’s DHCP off, but then the DHCP server on the modem wouldn’t assign IP addresses to wireless devices.

Tech support’s answer was that since I could get one computer to connect to the internet, the problem must be in my router, so it wasn’t their problem. (grrrrrrrrrr)

I’ve put the specific hardware to help others who are searching, but I think this basic solution will generally work for others who are having the same kind of issue.

The final answer that I finally found on a forum somewhere was this:

  1. Hook the ethernet cable to the dsl modem.
  2. Choose “Bridging mode” on the DSL modem for the network connection type. Click “next” through all of that. Reboot the DSL modem using the interface. You won’t be able to access the GUI after that, but that’s okay.
  3. Move the ethernet cable to your router.
  4. Hook an ethernet cable from the router’s “Internet” or “WAN” port to the DSL modem’s port.
  5. Configure it to use PPPOE and put in your ISP’s login settings.

…and it works like it’s supposed to, bridging the signal from the phone line to the ethernet line. The wireless router now handles NAT translation, DHCP, and so on.

Hopefully this will help someone else out there…

NETGEAR DSL MODEM DM111P
LINKSYS Wireless router WRT54G