dd-wrt linksys router con't connect to cable modem

crasher888

Junior Member
Sep 13, 2008
5
0
0
I'v got a linksys wrt 350n wireless router running dd-wrt firmware. I just moved and updraged from dsl to cable for my internet. When I connect the modem directly to any of my computers it works perfactly fine no problems and great speed. Yet when I connect the modem to my router and try and rebuild my network the problems begin. At first after I connected the router to the modem I couldn't get anything to work no ip address nothing. I did some reading around this board and tried cloaning the mac address of the modem. I finnaly got an ip address but once I connect to the router either wirelessly or directl with a cable once I open up my browser its jumps me directly to a mediacom, my isp, webpage asking for user account number and activation code. I called mediacom and got those numbers and codes I put them in and click the next botton it starts all over again. Mediacom says its a security mesaure they use to insure no one is illegaly trying to use a hacked cable modem to get free internet access and that there is something either wrong with my router or certant settings that need to be altered due to the dd-wrt firmware. I'v tried everything I can think of and nother works. I'm totaly stumped on this one and need some help please. I went to the dd-wrt forums but either no one is there or not willing to help. Any help would be greatly appreciated.

thank you
Gary
 

JackMDS

Elite Member
Super Moderator
Oct 25, 1999
29,471
387
126
In most cases Cloning the MAC address of the computer that can connect directly to the Modem to the Router solve Cable Internet authentication issues.

If media one has additional requirement they should b e transparent about it.
Their explanation that the Router is the problem does not make sense.

I do not know what are your options. If had other options I would cancel my service with them and switch to something else.
 

Engineer

Elite Member
Oct 9, 1999
39,234
701
126
Did you clone the MAC of your modem or one of the PC's connected? I'm not sure what cloning the MAC of the modem would accomplish.

As for the DSL to Cable, did you have the router connected to DSL and then move it to cable? If so, doesn't DSL typically use PPPoE? If that is the case, maybe the router needs to simply be reset to all defaults (hold in reset button for a few seconds until it lights up to reset).
 

VirtualLarry

No Lifer
Aug 25, 2001
56,340
10,044
126
I've seen those "walled garden"-type screens, when my friend had to replace his cablemodem. He had to call Comcast and give them the MAC address of the modem, and they added it to his account.

I'm not sure why your router is doing that, especially if you've tried multiple different PCs connected directly to the modem, and they all worked.

Unless they are recognizing the router's MAC, and not allowing it, because it's a router. That would seem a bit overly draconian though.

There should be no problem, if you took a PC, and hooked it up directly to the modem, and it worked, then if you hook that PC into the router, and clone the MAC address of the PC to the router, then it should work the same. Make sure that the router is configured for DHCP (that's usually the case with a cable ISP), and not PPPoE. Don't forget to reset the cablemodem, after changing connections with it.

Personally, it sounds like a configuration issue on their end, and to fix it, you just need to call them and supply the MAC of the device hooked into the cablemodem, and let them fix the database on their end.

Oh, and it seems like it would be pointless to clone the MAC address of the cablemodem into the router. I think that would just cause more problems. Clone the MAC address of the PC that worked plugged directly into the cablemodem instead.
 
Dec 10, 2005
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Originally posted by: VirtualLarry
Clone the MAC address of the PC that worked plugged directly into the cablemodem instead.

I have to do this with my Comcast service. The service was set up with my laptop's hardline connection, so I had to clone its MAC address for the router to work properly with the cable modem.
 

crasher888

Junior Member
Sep 13, 2008
5
0
0
alright did everything you said did a totaly hard reset of the router confirmed that it is set in automatic dhcp. For the mac address cloning I'v tried the wireless mac address for my laptop along with the wired card also put in the mac address of the network card for my other computer and the router could not get a connection at all. Yet when I put in the mac address of the actual modem the router will get an ip address yet once I connect a computer to the router and try and get on the web it still brings me to same verification screen as I described in my first post. I have one question that I don't know if it will fix it or not, but its something that poped in my head. Do routers have mac addresses for the wired portion and if it does how can i find the mac address of it so I can type that in for the mac address for it to clone? If no one else can come up with anything I'll head over to mediacom and exchange the modem for another one and see if that fixes it.
 

VirtualLarry

No Lifer
Aug 25, 2001
56,340
10,044
126
Try this:

Reset the router to factory defaults. Disconnect the router and put it aside.

Power down the cablemodem and PC, and plug your PC directly into the cablemodem (make sure that XP's firewall is enabled). Power up the cablemodem, wait 30-60 seconds, and power up the PC.

Type in "IPCONFIG /ALL" in a CMD prompt.

If it shows you an IP address, other than 169.x.x.x, or 192.168.x.x then you are getting an IP from the cablemodem.

Write down the MAC address of the NIC that was able to pull an IP.

Next, unplug the cablemodem, power it down and power down the PC, plug the router's WAN port into the cablemodem, plug the PC into the LAN port of the router, and power up only the PC and the router.

Go into the router's setup screen, and where you clone the MAC address, type in the MAC address that you wrote down.

Save the router config, and power down the PC and the router.

Now, power up the cablemodem, wait 30-60 seconds, power up the router, wait 30-60 seconds, and power up the PC.

Verify that the PC is getting an IP from the router by doing an "IPCONFIG /ALL" again from a CMD prompt. You should get a 192.168.x.x IP, and not a 169.x.x.x IP.

Next, log into the router, and check it's WAN config, and see if it is pulling an IP from the cablemodem.

Then, check if you have internet access, go to www.google.com in a web browser.

If it works, you can send me a check. :)
 

jeas74

Junior Member
Mar 15, 2014
1
0
0
I really appreciate all of you because today my Internet connection was replaced from DSL to Cable and it didn't work. I was trying one and other thing with no luck until I found this post and cloned my router's MAC address with the one of the PC that was tested (as some of you recommend here) and it immediately connected. Much appreciate it!!!
 

dealguru

Member
Jan 13, 2014
56
0
0
For Cable connections, cloning the MAC address usually does the trick. One important procedure after cloning is to do a power cycle to sync the whole system.