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No Connection With Xfinity Gateway and Unmanaged Switch

ebh7164
New Poster

No Connection With Xfinity Gateway and Unmanaged Switch

I have a CGM4140COM Xfinity Gateway and I am attempting to add an unmanaged gigabit switch to it so that I can connect some additional computers.  Since this is an unmanaged switch it should just be plug and play, but all the machines connected to the switch have no internet.  Windows 10 diagnosed the connection problem with an error that the connection is not valid.  All of the connection LEDs on the switch are on and blinking as if there is data passing through.

 

Thinking that this might be something with the switch itself I returned it and bought a different one, but still had the same issue.  I tried the cable from the gateway ethernet port to a laptop and it worked fine, but the moment I connected that laptop to the switch I had no connection.  Thinking that it might have been a defective cable (with some of the strands being broken) I bought a new cable, but that still gave me the same issue.  I've restarted the gateway as well as the machines numerous times, but still I have no connection.

 

This setup worked recently when I was using an old Apple Airport Extreme to act as a bridge, but I needed more ports than it offered and went with the switch, and that is when it started to give me issues.  I also have another unmanaged switch connected to the gateway's other ethernet port and that one works fine, a Hue Bridge, Harmony Hub and a NAS server are attached to that switch, and all are working.

 

I am at a loss for what might be the cause for this and I am open to any sort of suggestions.

jlavaseur
Valued Contributor

Re: No Connection With Xfinity Gateway and Unmanaged Switch

I believe the second port is used for connecting their Xfinity Home security and automation system(s). So you can only use the 1 port on that particular gateway/Xb6 to connect devices too

NoNoBadPuppy
Contributor

Re: No Connection With Xfinity Gateway and Unmanaged Switch

In order to use a second port, you will have to pay for a second IP address. I have a router with two ports, but only one is active because I am paying for only a single IP address.

 

 

EG
Expert

Re: No Connection With Xfinity Gateway and Unmanaged Switch


@NoNoBadPuppy wrote:

In order to use a second port, you will have to pay for a second IP address. I have a router with two ports, but only one is active because I am paying for only a single IP address.

 

 


That's incorrect. It's a combo modem / router gateway device, not a straight modem with two ports.



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ebh7164
New Poster

Re: No Connection With Xfinity Gateway and Unmanaged Switch

I found out the issue.  A friend and I worked on trying to isolate the issue and it appears that it was a dock for my laptop that was the issue.  It appears that when the devices were connected to the switch the adapter was causing connection issues.  I had restarted the laptop that it was on, but that had not resolve the issue.  It took me unconnecting the dock completely and connecting it back for the network to "clear out" so to speak.

 

I am now able to use the switch without issue and I have my desktop and laptop both running on ethernet connections.

 

Thank you to everyone who commented on this thread.

EG
Expert

Re: No Connection With Xfinity Gateway and Unmanaged Switch

Glad you got it figured out ! Now closing your topic.



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