Motorola Surfboard SB6121 Allowing One device.

Sephingx

Honorable
Sep 14, 2013
1
0
10,510
I have a Motorola Surfboard SB6121 Modem with a standard DLINK 10/100 mbps switch. There are currently two active towers on it. However, when I try to connect the ethernet cord from my tower and plug it into my laptop, xbox, or playstation, It won't connect to these devices without needing to reset. Although it wasn't always like this, I was able to do this with the same setup and setting as before.
 
Your ISP likely had something setup wrong and fixed it if this ever worked in the past.

This is why everyone who has a cable modem also has a router. Problem is people who don't have a clue use the terms interchangeably.

I am surprised you can get 2 devices to work most ISP limit you to a single IP that can be routed to the internet.

You need to buy a router or pay the ISP for more IP addresses.