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SG 300-20 and Service Electric cable modem


I am somewhat new to this level of networking and have run into a problem that I cannot seem to overcome...

I have an SG 300 switch that I had configured, and had working just fine, at my old residence using a DSL line. Since moving, I have changed over to a cable modem and find that my previous configuration does not work. Is there anything that needs to be changed since what I had set up worked before?

My current configuration is as follows:

Motorola Surfboard SB6121 connected to a Netgear WNDR4000. SG 300 (Layer 3) is configured with 5 VLANS, IP 10.1.x.1 for the interfaces and static route added to point traffic to (router). The router is configured with static routes back to the VLANs using as the return interface. The computers are all configured to use 10.1.x.1 as the default gateway, and have appropriate IP addresses in the same range.

I can ping everything internal, and can resolve names to IP on the internet, but cannot get a response, nor access any website on the internet. I have tried 2 different routers and 2 different cable modems, so that leads me to think that I have one or more settings incorrect on the switch.

If anyone can steer me in the right direction, I would truly appreciate it.

1 Reply 1

Tom Watts
VIP Alumni
VIP Alumni

Hi Matt, here is a topic I responded to a while back. This example uses a RV0XX router with a SX300 switch.

Please rate helpful posts

-Tom Please mark answered for helpful posts
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