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Posted by
New Visitor
Member Since: ‎06-29-2011
Posts: 3

New modem and old router problem

Hi folks,

After having some troubles lately I upgraded my old linksys modem to a new Motorola Xtreme. It is very fast and works fine connected to my PC.

However, I can't get it and my netgear wndr3300 wireless router to communicate. Reset and ran the wizard many times. This router was easy to config before. I wonder if there is an incompatibility between these devices.

Any ideas to help? Setup used to be Dynamic everything.

Thanks
Posted by
Cable Expert
Member Since: ‎03-02-2007
Posts: 13,291

Re: New modem and old router problem

First step is to power cycle the modem whenever you change devices on the WAN port.

 

When you change from having the pc connected to the modem to the router, you must power cycle the modem.  For users with a eMTA telephony modem, you must press the reset button on the eMTA.

 

If you are doing that and you still can't get connected, then post back, and there will be plenty of help.

Posted by
New Visitor
Member Since: ‎06-29-2011
Posts: 3

Re: New modem and old router problem

Thanks kudo. Yes, I reset the modem and it hasn't helped.
Posted by
Networking Expert
Member Since: ‎07-28-2003
Posts: 24,238

Re: New modem and old router problem

Try pulling both the power cord AND Ethernet cable on the modem and leave them unplugged for a minute or two. Then plug the power cord back in and let the modem stabilize. Then plug the router's Internet/WAN cable back in and power up the router.

If that doesn't work, make swapping out the Ethernet cable and make real sure it's in the proper WAN/Internet port on the router.

If still no joy, then describe how you are resetting the router. Make sure you use the documented reset to factory defaults procedure from the manual. Make sure that during setup you do NOT do any MAC cloning since that will require another modem power cycle. If still not working, post the exact WAN and LAN configuration on the router.
Posted by
New Visitor
Member Since: ‎06-29-2011
Posts: 3

Re: New modem and old router problem

Hi baric,

I've been just powering both devices on and off. I just did exactly as you described and no dice. I then repeated using a different cable and still no luck.

The router and cables were all working fine with the old modem. These two just don't want to negotiate.
Posted by
Networking Expert
Member Since: ‎07-28-2003
Posts: 24,238

Re: New modem and old router problem

I would definitely proceed with reseting the router to factory defaults then.  If still no dice, then post the router's config settings from http://192.168.1.1 so we can take a look.  It might be the router has failed.  Also post the output of ipconfig /all from your computer (assuming you have some flavor of Windows)

Posted by
New Visitor
Member Since: ‎12-12-2009
Posts: 1

Re: New modem and old router problem

Similar problem- slightly different though.

I installed a Motorola surfoard 6121 because speeds were slow 3-5 M and Toshiba was "end of life".

 

When connecting the computer directly to the ethernet out of the modem speeds are great- 25M.

When I connect the modem to the router  it won't do anything till I power down the modem and bring it back up.  Then it connects at 3-5 M as before.   

 

I have been powering down the router and powering up after the modem was running.

Any help is appreciated.

Posted by
Networking Expert
Member Since: ‎07-28-2003
Posts: 24,238

Re: New modem and old router problem


robermax wrote:

Similar problem- slightly different though.

I installed a Motorola surfoard 6121 because speeds were slow 3-5 M and Toshiba was "end of life".

 

When connecting the computer directly to the ethernet out of the modem speeds are great- 25M.

When I connect the modem to the router  it won't do anything till I power down the modem and bring it back up.  Then it connects at 3-5 M as before.   


Power cycling the modem is ALWAYS required when you switch the device connected to the modem.  The modem remembers the MAc address of the first device and will not talk to another until you reset it to a clean state where it can learn the MAC address of the new device.

Based on your description, it sounds like the router is the bottleneck.  What exact model of router?  How is the computer connected to the router, ethernet or wireless?  Can't really do anything without details.

 

In general, older routers (depending on model) can't keep up with the current modem speeds, they just aren't designed to handle this kind of throughput.  So stick with a router with gigabit ethernet interfaces (especially on the WAN/Internet post).  Such a device will be designed to handle high speeds and should not "get in the way" like an old router will.  

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