The mysterious Netgear Nighthawk CM1150V

[markaaron]

SERVICE. DEVICES. OPERATING SYSTEM
Internet Service:  Xfinity 500 Mbps

Modem:  Netgear Nighthawk Cable Modem with Voice (CM1150V)
Laptop 1:  Dell Latitude E7440
Laptop 2:  Dell Precision 7760
Cables:  Cat8 Ethernet

Operating System:  Windows 10 Professional

Everything is hardwired. I do not own a router. I do not use WiFi.

The Dell Latitude connected perfectly to the internet during the previous two years. However, I purchased a Dell Precision one month ago and, since then, the Latitude cannot connect to the internet. (The error message is the following: "Ethernet doesn't have a valid IP configuration"). However, the Dell Precision connects perfectly to the internet.

The problem is not computer hardware or software. The latitude connects perfectly to the internet at any location other than my home. As a last resort, my local computer tech person recently uninstalled and reinstalled Windows 10 Professional.

Does anyone have an idea what the cause of this problem might be?

Thanks in advance.

[Kitsap]

This is where the concept of a router comes in to play.  If you are trying to connect both of the laptop computers to the internet through the modem at the same time it will not work without a router.  Your ISP provides you with one IP address and it is taken by the one computer.  Some ISP's will provide you with a second IP address for an additional fee.

While you can connect a computer direct to the internet through the modem, it is not a good long term idea.  It exposes your computer direct to the internet without benefit of a firewall to protect it.

You do really need to buy a router.  If you do not want to use Wi-Fi, just turn it off.

Your Ethernet ports 2, 3, and 4 have very specialized uses.  Like link aggregation and a second IP address if your ISP supports a second one.

[markaaron]

Hello, Kitsap. Thanks for your reply.

I am attempting to connect only one laptop computer at a time through the modem. I am not utilizing Ethernet ports 2, 3, and 4. Here's the process:

Xfinity > Netgear CM1150V > Dell Precision 7760.  Result: Perfect connection. 

Then .....
1. Power down.
2. Unplug the ethernet cable from Dell Precision. 

3. Plug the ethernet cable into the Dell Latitude.

4. Power on.

5. Result. "Ethernet doesn't have a valid IP configuration"

By the way, the Precision and Latitude have ESET Internet Security installed. I have experimented with disabling ESET in the Latitude, but that has no effect. The result is the same, whether ESET is enabled or disabled..

Thoughts?

[plemans]

@Kitsap is correct. you need a router. 

The problem is xfinity. They only assign 1 public ip address per account. (unless you pay extra for more or have a business grade account).

Usually the procedure you followed works. But the problem is, sometimes it takes xfinity a while to reassign that public ip address. Again, its usually minutes but I've seen it take upwards of 30 minutes before during troubleshooting. 

Buying a cheap gigabit router and just disabling its wifi (or leave it enabled)  would fix your issue as you could connect as many devices as you wanted. You could get a generation or 2 old router off amazon or craigslist/fleabay for pretty cheap and you wouldn't have to fight the issue you're having. 

[Kitsap]

If you think ESET Internet Security or any other software based protection program is going to provide a level of security when directly connected to the internet, the only person you are fooling is yourself.  The design basis for software based computer protection programs is they operate inside a hardware firewall like provided with a router.

Your configuration of a computer connected directly to a cable modem is the basis for botnets, spam generators, and other threats to the internet.  Running such a configuration is irresponsible on your part.

Whether it is intentional or not, you are playing with fire and should stop.

[markaaron]

Hello, plemans. Thanks for your reply.

I purchased a Netgear 8-Port Gigabit Ethernet Unmanaged Switch (GS308). My original idea was this configuration:

Xfinity > Netgear CM1150V cable modem > Netgear Ethernet Switch > Dell Precision and Dell Latitude

That configuration doesn't work and, as I described above, bypassing the GS308 ethernet switch and connecting directly to the Latitude doesn't work either. I'm still not clear about why the Precision connects, but not the Latitude. But, at this point, I just want to get the Latitude connected. (It will serve as a backup). 

Could you, please, provide a couple of router recommendations? The most important feature, for me, is a physical, external switch that would allow me to turn off the wireless radios (not just the SSID broadcast), without interrupting my hardwired connection to the internet. I do not want to access router settings via the internet to accomplish this.

I'm not concerned about the cost of the router. This is for my work, and it's important to have a reliable, fast and stable connection.  My current Xfinity service is 500 Mbps, but I might upgrade the speed at some point.

Thanks again.

[FURRYe38]

FYI, the CM series of modems DO NOT have  a built in router. 

Xfinity > Netgear CM1150V cable modem > Netgear Ethernet Switch > Dell Precision and Dell Latitude< This will NOT work.

Xfinity > Netgear CM1150V cable modem >External Wifi Router> Netgear Ethernet Switch > Dell Precision and Dell Latitude< Will work.

[markaaron]

Thanks, FURRYe38. You Gurus are good. 👍

Can you recommend a good router? As I mentioned above, the most important feature, for me, is a physical, external switch that would allow me to turn off the wireless radios (not just the SSID broadcast) without interrupting my hardwired connection to the internet.

I receive a very large amount of fast, real-time streaming data during my work. The Precision has an i7 and 64GB RAM. And, I'm running two external monitors with a multiple monitor dock.

[FURRYe38]

Hmmm, Possible NGs RAX series might have something, like a RAX40 series. 

Another suggestion would be to have just a wired router only and then connect a wireless system in AP mode to the router. Then you might have more controls. 

You might reivew this forum and maybe post to users on there experiences with there RAX routers here:

https://community.netgear.com/t5/Nighthawk-Routers-with-WiFi-6-AX/bd-p/en-home-routers-nighthawk-wif...

@microchip8 Would be one to approach. 

[michaelkenward]

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@markaaron wrote:

Can you recommend a good router? As I mentioned above, the most important feature, for me, is a physical, external switch that would allow me to turn off the wireless radios (not just the SSID broadcast) without interrupting my hardwired connection to the internet.

---

Try plugging your needs into the filters on the product pages:

Wireless Routers for Home | NETGEAR

and

Orbi: Whole Home WiFi System for Better WiFi Everywhere | NETGEAR

Then check back here for reports on the things you are considering, but remember that people turn up in this community with problems, not compliments. So look at reviews on Amazon, for example.

[markaaron]

Thank you, michaelkenward!  Will do.👍