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Old 11-03-2012, 04:54 PM   #1
Oifish
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Default Only able to connect to Internet through modem

I was using the internet without problems then all of the sudden it wouldn't connect. I reset the router and modem but still nothing. I found that if I connect directly to the modem (Motorola SB5101U) I am able to connect to the internet without problems. My ISP is Brighthouse (RoadRunner). If I try to connect the modem to a router, I am unable to connect to the internet. I have tried two different Linksys WRT54GL both using DD-WRT and a Netgear WPN824 v2 and all three of them were not able to connect. I have no idea what to do. I called my ISP and they said nothing was wrong with the connection to the modem. Any help would be appreciated.
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Old 11-03-2012, 04:59 PM   #2
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When you change from having the computer connected directly to the modem to having a router connected to the modem(or the reverse), make sure you unplug the power on the modem so it will reset. Many of them are configured to only connect to the first network device it sees and won't connect to another until you unplug it.

If the router still doesn't work you could try resetting it back to the factory defaults then reconfiguring the Internet connection settings.
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Last edited by owensdj; 11-03-2012 at 05:01 PM.
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Old 11-03-2012, 05:27 PM   #3
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Bad cable?
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Old 11-03-2012, 05:40 PM   #4
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Your router may have gone bad on you. Check to be sure it's power unit is supplying the correct voltage to it (if it has an external power pack)
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Old 11-03-2012, 09:39 PM   #5
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Default mac address attack

Quote:
Originally Posted by Oifish View Post
I was using the internet without problems then all of the sudden it wouldn't connect. I reset the router and modem but still nothing. I found that if I connect directly to the modem (Motorola SB5101U) I am able to connect to the internet without problems. My ISP is Brighthouse (RoadRunner). If I try to connect the modem to a router, I am unable to connect to the internet. I have tried two different Linksys WRT54GL both using DD-WRT and a Netgear WPN824 v2 and all three of them were not able to connect. I have no idea what to do. I called my ISP and they said nothing was wrong with the connection to the modem. Any help would be appreciated.

any time you change the wire a cable modem is plugged into [IE computer to router, one router to another], you MUST power cycle the modem as it remembers the MAC address as the first device it talks to after it boots and will ONLY communicate with that MAC. Since each device has a UNIQUE mac, you will get nothing.

that said, the proper way to do this is power cycle the cable modem wait until it locks the online light [green in your case] then Ethernet to the NONPOWERED router, and power it up, wait a few minutes for it to do its boot sequence, then try to connect with a Ethernet cable first, if it goes online at that point, you can move to wireless. If you cannot connect by wireless you are probably doing something wrong, many laptops have an on/off swtich/key you accidentally can hit, etc...

Most routers come setup by default the way cable companies operate, so if you are getting used routers, I suggest holding the reset button down for 30 seconds, most of the time this resets them to default config.

Last edited by Cabletek; 11-03-2012 at 09:41 PM.
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Old 11-03-2012, 11:36 PM   #6
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30/30/30 reset? that would help as well.
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Old 11-05-2012, 05:28 PM   #7
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I needed to power cycle the modem, and 30/30/30 the router. After that the problem resolved. Thanks guys.
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Old 11-05-2012, 07:33 PM   #8
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Glad that worked for you, but with some routers you have to enable MAC Address Clone. Without that enabled, Road Runner modems won't work, period. If you need a new WAN IP address, manually change the MAC address in the router settings and reboot the modem.
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Old 11-05-2012, 08:02 PM   #9
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Quote:
Originally Posted by Oifish View Post
I needed to power cycle the modem, and 30/30/30 the router. After that the problem resolved. Thanks guys.
Glad to help!
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