Re: CM1200 Internet Speed Problem

julian12it · ‎2019-08-01

Hello fourm, I recently purchased a Nighthawk CM1200 Modem and a Nighthawk R6700 Router. The router was the first to arrive in the mail and I decided to set it up with my previous router. All was good with the router and my previous modem. Upon installing the new modem, the CM1200, I had to reset the router and attempted to power flush for it to retrieve the IPV4, Physical, & Mac address. Upon a rest and flush, the router wasn't retreiving the information from the modem. I called tech support and they kindly guided me through the process and got everything squared away.

The issue I'm having now is that with the router connected to the new CM1200 modem. When ever I have more than one port occupied on the CM1200 my internet speed flucuates eventually killing itself having the internet not work. Whenever the router is solo connected to the modem, everything works fine.

Overall, when I have my PC and router connected to the modem, it lags out killing itself in speed. When the router is solo connected, all is fine. Any suggestions on what can be done or should I return the modem for a new one?

CPLMayo · ‎2019-08-13

When you use more than one Ethernet port on the Cable Modem you are using LACP Link Aggregation which has been identified as an issue on the CM1200. You may want to post in the previous thread below with what you are seeing and which ISP you are using.

https://community.netgear.com/t5/Cable-Modems-Routers/CM1200-slows-down-after-24-48-hours-of-uptime-...

FURRYe38 · ‎2019-08-13

As mentioned before, the CM1200 has multiple ports for Link Aggregation and ISP specific IP address asignments. The only couple of routers that support LAG is the NG R7960P and R8000P. All other routers only support 1 port connection with the CM1200 with Port #1.

Be sure the LAG is disabled on the CM1200 modem.

@julian12it wrote:
Hello fourm, I recently purchased a Nighthawk CM1200 Modem and a Nighthawk R6700 Router. The router was the first to arrive in the mail and I decided to set it up with my previous router. All was good with the router and my previous modem. Upon installing the new modem, the CM1200, I had to reset the router and attempted to power flush for it to retrieve the IPV4, Physical, & Mac address. Upon a rest and flush, the router wasn't retreiving the information from the modem. I called tech support and they kindly guided me through the process and got everything squared away.

The issue I'm having now is that with the router connected to the new CM1200 modem. When ever I have more than one port occupied on the CM1200 my internet speed flucuates eventually killing itself having the internet not work. Whenever the router is solo connected to the modem, everything works fine.

Overall, when I have my PC and router connected to the modem, it lags out killing itself in speed. When the router is solo connected, all is fine. Any suggestions on what can be done or should I return the modem for a new one?

Dolvey · ‎2019-09-07

I just got off of the phone with support about my new CM1200 connected to a RAX80 router and was told that the additional ports on the CM1200 are useless and cannot be used if port aggregation is used, plus if you do not have multi-gig web service that the port aggregation will not work and that it is acting properly in choking off the internet speed because it is cheating to try to get a higher speed than for what you paid.

So Netgear WAN aggregation from router to modem is useless.

FURRYe38 · ‎2019-09-09

As mentioned before, the CM1200 has multiple ports for Link Aggregation and ISP specific IP address asignments. The only couple of routers that support LAG on there WANs is the NG R7960P and R8000P. All other routers only support 1 port connection with the CM1200 with Port #1.

Good Luck.

@Dolvey wrote:
I just got off of the phone with support about my new CM1200 connected to a RAX80 router and was told that the additional ports on the CM1200 are useless and cannot be used if port aggregation is used, plus if you do not have multi-gig web service that the port aggregation will not work and that it is acting properly in choking off the internet speed because it is cheating to try to get a higher speed than for what you paid.
So Netgear WAN aggregation from router to modem is useless.