Posts: 4
Registered: ‎05-31-2009

wrt54g2 and motorola cable modem sb5101 help please

I am trying to connect my wrt54g2 modem to a motorola sb5101 cable modem but i can't make it work.

I have followed all the instuctions here :


but it doesn't work what ever i do


when i connect with my computer directly to the modem is working fine,  but when i connect the router i have no internet.

in the status page, all the ip are 0, they don't change when i press dhcp release and renew.


It seems like the router can't take the ip from the modem

Posts: 6,365
Registered: ‎09-16-2006

Re: wrt54g2 and motorola cable modem sb5101 help please

What "Internet Connection Type" is the WRT54G2 set to?  It probably should be set to "DHCP - automatic".  Please set your router to this and then power cycle your entire network.


If the above does not fix your problem, then do the following:


1)  Please state your ISP

2)  Please do the following test:


Power down your entire network.  Using an ethernet cable, connect your modem directly to your computer.  (Do not use the WRT54G2 for this test.)  Power up the modem and computer.  Verify that you have a working Internet connection, then proceed with the following:  (Even if your Internet connection does not work, state this, and proceed.)


Go to "Start" > All Programs > Accessories > Command Prompt.
A black DOS box will appear. Type in "ipconfig /all" (with no quotes), then hit the Enter key.   Copy all the results to your next post.  To do the copy, highlight the results, then use the copy (Ctrl-c) keys and the paste (Ctrl-v) keys.  If your "IP address" does not start with 192.168 , then for security reasons, erase the last half of your IP address.



Posts: 4
Registered: ‎05-31-2009

Re: wrt54g2 and motorola cable modem sb5101 help please

Router is already set up in DHCP Automatic


Windows IP Configuration

        Host Name . . . . . . . . . . . . : supervis-i0xl8t
        Primary Dns Suffix  . . . . . . . :
        Node Type . . . . . . . . . . . . : Unknown
        IP Routing Enabled. . . . . . . . : No
        WINS Proxy Enabled. . . . . . . . : No
        DNS Suffix Search List. . . . . . :

Ethernet adapter Local Area Connection:

        Connection-specific DNS Suffix  . :
        Description . . . . . . . . . . . : Intel(R) PRO/100 VE Network Connection
        Physical Address. . . . . . . . . : 00-08-02-67-B3-3F
        Dhcp Enabled. . . . . . . . . . . : Yes
        Autoconfiguration Enabled . . . . : Yes
        IP Address. . . . . . . . . . . . :
        Subnet Mask . . . . . . . . . . . :
        Default Gateway . . . . . . . . . :
        DHCP Server . . . . . . . . . . . :
        DNS Servers . . . . . . . . . . . :    


I have changed the last nubmers on ip address with xx


Thanks for the reply

Posts: 2,766
Registered: ‎09-07-2006

Re: wrt54g2 and motorola cable modem sb5101 help please

I believe the IP Configuration you provided is when you connect your computer straight to the modem...

Make sure when you connect your computer to the router you get the IP Address : 192.168.1.x, Subnet mask :, Default Gateway :


Open an Internet Explorer browser page on your wired computer(desktop).In the address bar type - and press Enter...Leave username blank & in password use admin in lower case...

Click on MAC Address Clone and Enable it, enter this MAC Address : 00-08-02-67-B3-3F manually and do not click on Clone, click Save Settings, click Status, check the value of the Internet IP Address. If the Internet IP Address has numbers, this means the router has been properly configured. You should now be able to access the Internet. If you’re not online, perform a power cycle to synchronize the router with the modem...

Posts: 3
Registered: ‎06-01-2009

Re: wrt54g2 and Webestar cable modem sb5101 help please

Hey!  I have also this same problem.  I configured my WRT54g2 as Automatic configuration DHCP mode and clone with my PC.  In the status result shown the ISP IP address and everything is fine.  But internet connection keep disconnecting.  If I did a power cycle it will be working for a few time.  I connect my PC direct to the modem (Webstar cable modem) and it's working fine.  I made many power cycles in modem, router and pc.  Also I upgrade the firmware with But still the result is same.


I check with my ISP and everything is Ok from their side.


Could any one help me?



Posts: 6,365
Registered: ‎09-16-2006

Re: wrt54g2 and motorola cable modem sb5101 help please

[ Edited ]

to manos  -- 


Your router should work when you have reset it to factory defaults, except you might have to clone the MAC address of your computer, into your WRT54G2.


So please do the following:


To reset your router to factory defaults, use the following procedure:

1) Power down all computers, the router, and the modem, and unplug them from the wall.
2) Disconnect all wires from the router.
3) Power up the router and allow it to fully boot (1-2 minutes).
4) Press and hold the reset button for 30 seconds, then release it, then let the router reset and reboot (2-3 minutes).
5) Power down the router.
6) Connect one computer (use the same computer that works when you wire it directly to your modem) by wire to port 1 on the router (NOT to the internet port).
7) Power up the router and allow it to fully boot (1-2 minutes).
8) Power up the computer (if the computer has a wireless card, make sure it is off).
9) Try to ping the router. To do this, click the "Start" button > All Programs > Accessories > Command Prompt. A black DOS box will appear. Enter the following: "ping" (no quotes), and hit the Enter key. You will see 3 or 4 lines that start either with "Reply from ... " or "Request timed out." If you see "Reply from ...", your computer has found your router.
10) Open your browser and point it to This will take you to your router's login page. Leave the user name blank, and in the password field, enter "admin" (with no quotes). This will take you to your router setup page. Note the version number of your firmware (usually listed near upper right corner of screen). Exit your browser.

If you get this far without problems, power down your entire network.  Connect the ethernet port of your modem to the Internet port of the WRT54G2.   (Note: Do not connect anything to the USB port of the modem.)    Leave the computer connected to port 1 on the WRT54G2.  Power up your modem and  allow it to fully boot (1-5 minutes).  Power up the WRT54G2 and allow it to fully boot (1-2 minutes).  Power up your computer.  Try to connect to the Internet.  If you have a problem, temporarily turn off your computer software firewall, and try again.


If you still have trouble connecting, power down your modem.  Next login to your WRT54G2 at  and clone the MAC address of your computer into the router.  Power down the WRT54G2 and the computer.  Wait one minute.  Next, power up your network (same method as in previous paragraph), and try again to connect to the Internet. 

If you cannot get "Reply from ..." in step 9 above, your router is likely dead. Report back with this problem

If you get a reply in step 9, but cannot complete step 10, then either your router is dead or the firmware is corrupt. Report back with this problem.

If you need additional help, please state the results of steps 9 and 10. Also, if you get any error messages, copy them exactly and report back.

Please let me know how things turn out for you.

Message Edited by toomanydonuts on 06-02-2009 01:28 AM
Posts: 4
Registered: ‎05-31-2009

Re: wrt54g2 and motorola cable modem sb5101 help please

I have already  tried all the above, but nothing

have already upgraded the router's firmware to the latest version  and I have copied the mac address (I just clicked on clone I did't enter it manually).

When everything is connected I can ping the router and access the setup pages.

The only things I haven't tried yet is to turn off my firewall, enter my mac address to the router manually and when I do a powercycle I don't  unplug it from the wall.

I will try later because I am not at home right now,


Thanks again

Posts: 75
Registered: ‎05-31-2009

Re: wrt54g2 and motorola cable modem sb5101 help please

Good day!


There are certain modems like cable that most ISP's have you set up for USB connection. It is possible your main computer is connected and online thru the modem using USB connection. One thing for sure that the router only supports Ethernet connection. With this, you may need to contact your ISP and have your modem setup to work with Ethernet and that  your main computer also have an Ethernet card.


Also, there are modems installed with DOCSIS 3.0 and most Linksys routers are having issues with this configuration. You may encounter intermittent or frequent disconnection, or unable to establish a connection at all. Not all Linksys products supports this and normally works when putting a switch in between the modem and the router. This may be causing to fry the router.


I know, this information is more on higher level of the configuration but who knows this might be the problem you are having right now.


For heads up!



>>> call me jam <<<

Posts: 75
Registered: ‎05-31-2009

Re: wrt54g2 and motorola cable modem sb5101 help please

Also, I'd like to add something. It could be the router's Internet port is defective, it may not be able to get an IP or connnection from the modem.


For testing, do the following:


> Press and hold the Reset button at the back of the router for 30 seconds while it is power on. Then proceed with this steps:

1. Get 1 Ethernet cable, connect the first end to the Internet port of the router then the other to port 1.

2. Connect your PC to port 4 of the router. Power up the PC and router. Make sure power light on the router is steady, port 1 and 4 are lit, and Internet light is on.

3. Check the IP address of the computer wired to the router. To do that, open Command Prompt for Windows and type ipconfig/all. It will be in range.

4. Once it has confirmed with a valid IP Address, logon to the router's setup page thru , Username is blank and default Password is admin. You have to use Internet Explorer browser for this.

5. Click on Status tab and check on Internet Connection portion if it has an IP address like This means the router's Internet port is working fine.


> If none of this works, better contact Linksys Technical Support thru 1-800-5465797 or thru Live Chat for assistance.


There is a possibility that you have a faulty router.


For heads up!



>>>call me jam<<<

Posts: 4
Registered: ‎05-31-2009

Re: wrt54g2 and motorola cable modem sb5101 help please

[ Edited ]

I did everything from beggining, and now it is working fine.

On the status page I can see now my provider ip

This is what i did exactly if anybody else has the same problem.


1. Router reset

2. Copied mac address manually to the router (didn't press the clone button)

3. Power down router

3. Power down modem and unplug from wall

4, Power down computer

5. Power up modem

6. Power up router

7. Power up computer



I believe that the difference is that I entered my mac address to the router manually, as all the others procedures I had done again and again and I think I remember that the last digit on the mac address when i clicked on clone was 7 not f.


Thank you all


Message Edited by manos on 06-02-2009 08:58 AM