Netgear Night Hawk CM1100 does not work with Google Nest Wifi, any guidance? Xfinity gigabit plan

[ColinZ]

Hi everyone,

Asking for some desperate advice here as I have spent the entire weekend googling and reseraching, and still have no luck.

I got the brand new Netgear Night Hawk CM1100 (DOCSIS 3.1) from Costco. It is a simple modem only. No router capability whatsoever. I am on the Xfinity Gigabit Internet plan and have been using Xfinity over the past two years. Recently upgraded to the Gigabit plan from 200Mpbs due to SIP and COVID work from home arrangement. For the life of me, I could not get Google Nest to work with the CM1100. I deleted my previous network setup, and now I can't even set up a new device (Google Nest Router or Access Point) as the device setup process would fail ever single time. After 20+ attemtps, I get 3 different kinds of errors and was never able to complete the setup process for Google Nest Wifi in my Google Home App. Error 1) Connection to Device Failed 2) Google Nest Router could not create a network 3) No connection to the cloud. The CM1100 is NOT a modem/router all in one, so there is no double NAT or routing issues. I restarted the modem and router in the correct sequence multiple times per other posts' recommendations, same results.

My previous setup: 

Internet Plan: Xfinity 200Mpbs internet

Modem: arris surfboard sb8200

Router: Google Nest Wifi

My current setup:

Internet Plan: Xfinity 1000Mpbs internet

Modem: CM1100

Router: Google Nest Wifi

I called Xfinity and they did various checks and validated the modem is working perfectly. They see the modem, see a strong signal, and can remotely restart the modem. When I swap out my Google Nest Wifi Router with my old Apple Airport Extreme router, everything works perfect. So I know the root cause is with the interaction between CM1100 modem and Google Nest router. 

Someone at the Costco product review webpage recommended adding a network switch between the modem and router to make it work betweeh the CM1100 and Google Nest wifi, but that seems like an odd configuration, so I am not sure if that would solve it. Although I did order a switch from Amazon just in case. Will try that in a couple of days when it arrives. 

Has anyone else seen similar issues? At this point, I am running out of all options. Would love and appreciate any tips you could help share!

[pmiller79]

This issue sounds similar to my issue. I also have a gigabit plan. Does your Google Nest Wifi acquire a public IP address from the modem?

https://community.netgear.com/t5/Nighthawk-Pro-Gaming-Routers/Difficulty-obtaining-a-public-IP-addre...

[plemans]

There's not much for settings on the cm1100. 

A couple things to try. 

1. Make sure port aggregation isn't enabled on the cm1100

2. try connecting a pc directly to the cm1100 to see if it works

3. power off the cm1100 and disconnect it from the coax. factory reset the google wifi.  reconnect the cm1100 to the coax and power it on. give it several minutes. Then connect the google wifi to it and power the google wifi on and attempt setup with just the 1 hub. 

something else. The cm1100 has 2 ethernet ports but for xfinity, only 1 port is usable unless the router supports wan port aggreagtion (google doesn't as far as I know). So make sure only 1 device is connected to the cm1100 and ensure its on port 1. 

which google wifi is it?

[ColinZ]

Thanks for the reply, pmiller! The URL link was cut short when posted but I was able to find the full URL link via the search on the community form. But it looks like the page expired and the link no longer works. Would you please kindly post the solution that worked for you or perhaps repost the full link again at the beginning of the message? Thanks so much!

[ColinZ]

Thank you, plemans! 

I carefully followed your guidance and still could not get to a working solution. I am ready to return the Netgear CM1100 and purchase the Arris SB8200 instead. 

1. I validated teh port aggregation isn't enabled on the cm1100. Just to be 100% sure, I actually changed to port aggregation, restarted the modem, and changed it back to disable port aggregation, and then restarted the modem.  

2. Yea, when I tried connecting a pc directly to the cm1100, it works perfectly. I also tried connecting my old Apple Airport Extreme Router to the CM1100, and it works well. Must be something wrong with the interface between the cm1100 and the Google Nest Wifi. 

3. Yea, while focusing on just the Google nest router and not any of the points, I did go through the power cycles and power off-restart sequence per instruction, still not working. The further step I got to was Google Nest Wifi was trying to set up the wifi network with name and password and then it just pukes as the wifi network creation fails every single time. 

And yes, I was using the LAN1 port on the cm1100 and had nothing in the LAN2 port. The Google wifi system I am using was the bundle package purchased from Costco back in April (1 router and 3 points), and I believe it's the latest generation as of Summer 2020. 

Lots of people mentioned their Google wifi does not work with cm1100 but there were some other people who said it would work. Looks like a 50-50 success rate to me so far. However, I have not been able to get it to work and plan to make the return this weekend. 

[FURRYe38]

I would make contact with Google support and get additional help and information regarding there router wifi product. They should have information you need to get there router connected. Just be sure your connecting the router with a good quality LAN cable to port #1 on the CM1100 modem. A power off of the modem and router should be done for 1 minute then back on. Wal thru Google routers setup wizard and see if it will get it setup with the modem. If other wifi routers are connecting to the CM modem and the Google one isn't, then the Google router maybe faulty. Something to ask Google about. 

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@ColinZ wrote:

Thanks for the reply, pmiller! The URL link was cut short when posted but I was able to find the full URL link via the search on the community form. But it looks like the page expired and the link no longer works. Would you please kindly post the solution that worked for you or perhaps repost the full link again at the beginning of the message? Thanks so much!

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[pmiller79]

Hi ColinZ. I am still looking for a solution. You should be able to click on this link.

[SMW-308]

I have the same problem. I successfully added my Google wifi to the CM1100 and it was working fine. I was having some speed problems with my ISP (Cox) and the ISP performed a "hard line" reset of the router (not a mere power reset). It fixed my speed problems but my Google wifi would not connect to the internet, eventhough it is directly wired to the LAN 1 connection. I ran through the troubleshooting posted on the Google help site and other forums (disconnect power to the modem and wifi, wait a few minutes, reconnect power to the modem, once the modem is operating fully, connect power to the Google wifi). I have completed this procedure several times with no success. My devices are connected to the wifi but cannot reach the internet.

From all of the community forums I have read, this appears to be a problem with the CM1100 modem, not the Google wifi. If I cannot solve this, I plan to return my modem since I have not seen posts that indicate similar problems with other modems. That would be a shame.

Any help on this is greatly appreciated!

[FURRYe38]

Have the ISP check the signal and line quality UP to the modem. Be sure they have provisioned the modem correctly.
Be sure there are no coax cable line splitters in the between the modem and ISP service box. 
Be sure your using good quality RG6 coax cable up to the modem. 
Be sure to power OFF the modem for 1 minute them back ON.
https://community.netgear.com/t5/Cable-Modems-Routers/General-info-and-Troubleshooting-for-Cable-Mod...

Power OFF the CM modem and connect 1 wired PC or laptop to the WAN port #1. Remove wifi router for now. Power ON the modem. Check to be sure the computer gets internet services here. 

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@SMW-308 wrote:

I have the same problem. I successfully added my Google wifi to the CM1100 and it was working fine. I was having some speed problems with my ISP (Cox) and the ISP performed a "hard line" reset of the router (not a mere power reset). It fixed my speed problems but my Google wifi would not connect to the internet, eventhough it is directly wired to the LAN 1 connection. I ran through the troubleshooting posted on the Google help site and other forums (disconnect power to the modem and wifi, wait a few minutes, reconnect power to the modem, once the modem is operating fully, connect power to the Google wifi). I have completed this procedure several times with no success. My devices are connected to the wifi but cannot reach the internet.

From all of the community forums I have read, this appears to be a problem with the CM1100 modem, not the Google wifi. If I cannot solve this, I plan to return my modem since I have not seen posts that indicate similar problems with other modems. That would be a shame.

Any help on this is greatly appreciated!

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[Malena519]

I cannot connect the Google nest either. I deleted both the Google WiFi and the Home app, reset the nest to factory defaults, nothing helped. Extremely frustrating! Of course nobody in Customer Service at Google is available. I am going back to my old modem tonight so my daughter can attend class in the morning. After school, I will reach out to Google Neat CS and See of they are able to help. If not, the Nest goes back to Costco. The modem stays.

[FURRYe38]

When connecting a wifi router to the CM modem, power OFF both modem and router for 30 seconds, then power ON the modem, then power ON the wifi router. The router should get connected to the modem. Review the routers user manual on how to check status on the WAN or Internet port of the router. 

Be sure your using good quality LAN cables. CAT6 is recommended. 

Be sure LAG is disabled on the CM modem.

Try a different router with the CM modem as well. 

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@Malena519 wrote:
I cannot connect the Google nest either. I deleted both the Google WiFi and the Home app, reset the nest to factory defaults, nothing helped. Extremely frustrating! Of course nobody in Customer Service at Google is available. I am going back to my old modem tonight so my daughter can attend class in the morning. After school, I will reach out to Google Neat CS and See of they are able to help. If not, the Nest goes back to Costco. The modem stays.

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[SMW-308]

My experience was frustrating too because I spent hours with Cox cable and reearching issues with Google Nest with no solution. My problem was solved once I called Netgear.

I made the assumption that I could use both of the Ethernet connections on the back of the modem to connect to the internet. Netgear told me that for my internet service (0.5 G) I should only use one (either) of the connections. So, the service comes into the Netgear modem, is connected to the Google Nest router, then goes from the router to a switch that provides the connections to all my other cabling. The two Netgear Ethernet connections are used for a 1.0+ G configuration that I do not use. Pretty simple, right?

This may not be your situation but once I used this configuration, everything worked. Be sure that the internet (globe) icon on the Netgear modem is solid before you power up the Google Nest.

Hope this helps.

[SMW-308]

BTW -- After powering down the modem, wait about 5 minutes. Seems excessive but powering up after a minute sometimes did not work.