Bad RT66u?

[dazz87]

Got my RT66U last week and it took an hour trying to get a IP address from my cable modem. Finally got it to work, and over the weekend I was had to clean up some wiring. Unplug the cable and again I couldnt get the router to connect to my modem. I had to re flash to Asus stock firmware in order for it to connect (get a ip address) This morning the cable guy come out and was working on the cable box (TV) and had to unplug the router from the modem to work on it. Plugged the modem back and no internet connection. Could this be a bad router? dont know why it keeps on losing the ip address. Ever had an issue with my previous router.

 

[RMerlin]

Make sure the ethernet cable between the modem and the router is CAT5e or CAT6.

Try powering off your modem for 5-10 mins to fully reset its connection with your ISP.

See if your ISP requires you to use MAC cloning on your router (some ISPs do, most don't).

 

[andy_113]

I had this problem when i first got mine (virgin media super hub in modem mode), i think it might be a stock firmware bug because toastmans tomato has never had it, and i've also tried asus latest firmware which worked fine, so it's worth making sure you have the latest firmware. Hope this helps

 

[dazz87]

Make sure the ethernet cable between the modem and the router is CAT5e or CAT6.

Try powering off your modem for 5-10 mins to fully reset its connection with your ISP.

See if your ISP requires you to use MAC cloning on your router (some ISPs do, most don't).

Hey RMerlin, I had try unplugged the modem for that long of a period and still nothing. Charter (my ISP) does not require a mac cloning. Over the weekend when it was unplug the router has your firmware and it couldnt connect. I had to download the stock firmware. At 60% into the flashing the firmware the internet connection icon change from not connect to connect. You know what I have another one coming from amazon and hopefully this new one is much more stable then the one I have now.

 

[RMerlin]

Hey RMerlin, I had try unplugged the modem for that long of a period and still nothing. Charter (my ISP) does not require a mac cloning. Over the weekend when it was unplug the router has your firmware and it couldnt connect. I had to download the stock firmware. At 60% into the flashing the firmware the internet connection icon change from not connect to connect. You know what I have another one coming from amazon and hopefully this new one is much more stable then the one I have now.

I would check the WAN cable then to make sure it's not an older Cat5. I've seen many users resolving WAN stability issues by replacing that cable.

Otherwise, look into the System Log page for hints as to what is happening when it tries (and fails) to connect.

 

[SoCalReviews]

Hey RMerlin, I had try unplugged the modem for that long of a period and still nothing. Charter (my ISP) does not require a mac cloning. Over the weekend when it was unplug the router has your firmware and it couldnt connect. I had to download the stock firmware. At 60% into the flashing the firmware the internet connection icon change from not connect to connect. You know what I have another one coming from amazon and hopefully this new one is much more stable then the one I have now.

I doubt the problem was with the firmware or the Asus router. I have had a similar problem you are describing after my cable internet connection had been down for maintenance. The router didn't seem to be obtaining a WAN IP address from the modem possibly because the modem wasn't obtaining a new one. While it had worked at times in the past only unplugging the router for ten minutes didn't work this time. Customer support for the cable internet service suggested that I also try fully disconnecting the coaxial cable itself from the modem while the modem is powered off for ten to fifteen minutes. I don't know why this would work or if it was just a coincidence those times when it worked for me but this extra procedure did work. The Ethernet cable I use between the cable modem and the router is Cat7 S/STP (shielded/shielded twisted pair) and as Merlin indicated a cable specified as Cat5e or better is recommended.

 

[dazz87]

I would check the WAN cable then to make sure it's not an older Cat5. I've seen many users resolving WAN stability issues by replacing that cable.

Otherwise, look into the System Log page for hints as to what is happening when it tries (and fails) to connect.

I tried newer cable and it was the same. Well, my new RTN66 came today, quick question. When i get it up and running could I go ahead and flash it to 3.0.0.4.260.21 right away, or do I have to do the asus update (firmware) first? I believe the latest batch from Asus is one firmware behind the current firmware.

 

[dazz87]

I doubt the problem was with the firmware or the Asus router. I have had a similar problem you are describing after my cable internet connection had been down for maintenance. The router didn't seem to be obtaining a WAN IP address from the modem possibly because the modem wasn't obtaining a new one. While it had worked at times in the past only unplugging the router for ten minutes didn't work this time. Customer support for the cable internet service suggested that I also try fully disconnecting the cable itself from the modem while the modem is powered off for ten to fifteen minutes. I don't know why this would work or if it was just a coincidence those times when it worked for me but this extra procedure did work.

Weird thing is that IF I plugged in my notebook straight into the modem I got the Wan IP right away. With the router it took some time to obtain the new WAN IP

 

[SoCalReviews]

Weird thing is that IF I plugged in my notebook straight into the modem I got the Wan IP right away. With the router it took some time to obtain the new WAN IP

We know the cable company has to provision the cable modem for its system. When I first set up my cable internet I experienced the connection working when I plugged a notebook directly into the modem but it didn't work when I plugged the router into the modem. It was strange because when I was testing it at some point I knew I had the router working when it was connected to the modem. I was using a Netgear WNDR3700v2 router at the time I experienced this same issue.

I don't know exactly what is happening but I theorize that the modem obtains the MAC address of the device plugged into it and it may also forward that information upstream to the cable company's servers. If the WAN IP from the cable company changes or if the internet connection from the cable company goes down then it may be that the entire communication and device authentication has to restart and reconfigure.

If you change the device that is plugged into the cable modem such as going from your notebook to the router or back then a complete reset of the modem and a WAN IP address reset on the cable company side might have to take place. This may be why disconnecting the cable modem for ten to fifteen minutes usually works because the cable ISP server must have time to reset its information about what is connected to its system (possibly the MAC address of the device connected to the cable modem...whether that device is a notebook or a router) before providing a new WAN IP address to the modem and the modem provides that WAN IP to the router, notebook or other device plugged into that modem.

 

[RMerlin]

I tried newer cable and it was the same. Well, my new RTN66 came today, quick question. When i get it up and running could I go ahead and flash it to 3.0.0.4.260.21 right away, or do I have to do the asus update (firmware) first? I believe the latest batch from Asus is one firmware behind the current firmware.

You can directly flash the latest Asuswrt-Merlin.

SoCalReviews's point is a good one as well. With cable modems, you usually have to keep the modem unplugged for 5-10 mins, or otherwise it might have troubles (or flat out refuse to) assign a new DHCP lease to your router.

 

[dazz87]

You can directly flash the latest Asuswrt-Merlin.

SoCalReviews's point is a good one as well. With cable modems, you usually have to keep the modem unplugged for 5-10 mins, or otherwise it might have troubles (or flat out refuse to) assign a new DHCP lease to your router.

Thanks. Took 10 minutes to setup my new RT66. 2 mins to get Wan IP, flash latest Asuswrt-Merlin in 3 minutes. Then setup the config page. Hopefully this router will be more stable then the previous one.

 

[TonyH]

Hi,
In a case like that I would bypass router and connect a PC NIC directly into the modem, then it'll show what is going on. Another thing to try is
using ping and ipconfig command to se what is happening.