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Doug_K's avatar
Doug_K
Follower
Nov 22, 2019

Ooma Telco and Nighthawk CM2100

Guys-

I know this is the wrong board to post in.

NetGear web site didn't have board option for direct questions regarding the cable modem itself and its LAN Ports.

 

Here goes....

My Nighthawk CM1200 is a cable modem with four LAN Ports.

Learned not to use LAN Port 2 since I have Ethernet Port Aggregation disabled.

Plugged my Ooma Telco into LAN Port 4.

 

My Problem:

Ooma not able to recognize Internet access. Just sits and blinks.

Tried all the various turn on / turn off / reset combinations - no luck.

Any insights / suggestions?

 

Ooma worked fine with my Arris Modem.

Swapped out the Arris, put the Nighthawk on-line, and now I'm stuck.

2 Replies

  • FURRYe38's avatar
    FURRYe38
    Guru - Experienced User
    Dec 18, 2019

    You need a router berween the CM modem and your Ooma device still. The other LAN port are not for IP addressing LAN side devices. There for ISP WAN side IP address assignments. Connect a external wifi router to the CM modem and then connect your devices to the wifi router. 

  • antinode's avatar
    antinode
    Guru
    Dec 18, 2019

    > I know this is the wrong board to post in.

     

       I'm pretty confident that a cable modem like the CM2100 qualifies
    under "Cable Modems & Routers".

     

       Sadly, despite Netgear's elaborate claims for its capabilities, it's
    a modem, not a router, nor does it incorporate one, so you probably
    can't use it for multiple client devices unless you connect it to (only)
    a NAT router.

     

       A quick web or forum search for your (actual) model number should
    find abundant reports like yours, from folks who (thanks to potentially
    misleading claims) misapprehended the utility of the multiple LAN ports
    on the CM2100.

     

       Visit http://netgear.com/support , put in your (actual) model number,
    and look for Documentation.  Get the User Manual.  Read.  Look for "LAN
    port".  Do you see anything which suggests any use of ports 3 or 4, or
    any use of port 2 other than for port aggregation?


    > Ooma worked fine with my Arris Modem.

     

       What was your "my Arris Modem"?  My guess is that it was a
    modem+router (gateway), not only a modem (like the CM1200).