I have an Arris TM722G/CT modem and a Linksys WRT54GL router that has worked without issues for months. Recently, I have been unable to access some websites, like my banking site or college site, or make or receive voice calls through Skype. I can IM through Skype, but not place voice calls. If I connect my laptop or PC directly to the modem, bypassing the router, full access is restored. Thinking that perhaps my router was dying, I purchased a new Linksys E1200. I have the exact same problem with the E1200!. I have tried power cycling the modem, and the router, and rebooting the laptop and PC multiple times. I've removed the lithium ion battery pack from the modem, and held the reset button, and power cycled the modem to no avail. I've tried cloning the Mac address of the laptop to the router in the setup page, and the problem persists. Has Comcast made some change that now shuns Linksys router owners? Any ideas? Should I give up on Linksys and try another router?
I no longer have VOIP, and have no need for a telephony modem. Perhaps the modem is causing the issue, and I'd be better off with the Motorola SB6120 or SB6121?
Likely a firmware issue on the router. I have heard about problems with some E1200, it's not a device I'd recommend, I'd prefer the E3200. Always stay away from the botom of the pile models in any lineup, there's a reason they are "inexpensive". However, you can updating the firmware, go to:
Click on Downloads, select your hardware verions (1 or 2) and get the latest firmware. Make sure you get the right hardware version or you can brick your router. After you update the firmware, reset it to factory defaults and re-apply your settings.
As for changing the modem, it's not likely to do any good since things work when the computer is direct connected. Also, if you have the Arris TM722G, you likely have Xfinity Voice, yes? If so, the Motorolas won't work for you, at least not by themselves, they are not EMTA's and have no telephone ports.
I now only have cable internet. No longer have voice services, or TV through Comcast, so I could ditch the Arris modem, if that would help.
I updated to the latest firmware on the WRT54GL, and it had no effect on the issue. Some websites will load. Some won't. Can't make Skype calls, but I can IM through Skype. The E1200 has the same problem, same sites won't load, same issues with Skype. The E1200 already has the latest firmware (hardware version 1), and it's brand new out of the box. I went through the powercycle procedure on Comcast's "Home Networking 101" page multiple times.
It's odd that the WRT54GL worked for so long, and suddenly this issue occurs, and a brand new E1200 has the exact same problem. Makes me think something changed on Comcast's end.
Went back to Wally World and picked up a Netgear N600 (WNDR3700v2), power cycled the modem, after hooking up the router. Then powered on the router, then booted the laptop. The same issue persists! I did an ipconfig/all in the cmd prompt window, and oddly the "default gateway" is blank, when it should be 192.168.1.1 (the internal IP of the router), right? Going to try manually adding the gateway in network adapter settings...
It would help here if you posted the the full output of "ipconfig /all" when direct connected to the modem and when connected through the router.
And yes, when connected to the router, your connection's default gateway should be the IP address of the router. It's possible to work without that depending on the router handles things, but it's definitely odd. The Netgear WNDR3700 is a nice router, well regarded and seems to work very well for a lot of folks, it's a nice choice vs the E1200. You might want to reset it to factory defaults, just to make sure it's clean, see the manual for the exact procedure.
With a TM722G, power cycling is NOT going to help, it has an internal battery (so you don't lose phone service during a power outage), use the Reset button on the back instead. I see no reason currently to ditch the modem unless you want to pick up your own and drop the $7/mo rental fee which sounds like a good idea to me. The Motorola SB6120 and SB6121 are nice (I use an SB6120).
I get the "server not found" message when trying to load my college site. Oddly, my banking site will come up behind the Netgear router, but not behind either of the Linksys routers. I still can't make Skype calls behind any of the routers. Can't even call the echo test service.
I'll try manually adding those DNS servers and see what happens. The DNS servers listed in the router are currently 220.127.116.11 and 18.104.22.168.
That all looks for a direct connected computer. What about the output when connected behind the WNDR3700?
I notice you have an IPv6 address as well. When your hook the router back up, disable the IPv6 support in the router (not the PC) and see if that makes a difference. If not, then disable it on the PC when behind the router and try again. Instructions from Microsoft are here:
I've tried both taking the battery out and unplugging the modem (which Comcast's site says not to do..found this after doing it ), and leaving it powered up and hitting the reset button.
I downloaded the manual for the Arris TM722G/CT modem, and under troubleshooting, it says to use a cross-over ethernet cable when connecting to a hub or home router?? I've been using a regular ethernet cable all this time, and it's worked fine for a couple of years. Could this be the problem? I thought routers did this crossover thing internally?
I also tried going into the network adapter settings in Windows 7 and manually adding the gateway as 192.168.1.1...didn't help.
The Netgear router is new out of the box...it was already factory defaults. I ran the setup CD when installing it though. I still have the issue on my laptop, PC, and even my smartphone when trying to access those sites or make Skype calls behind the router. Which makes a software issue on my end seem unlikely. Comcast tech support says no settings are changed on their end when you add a router. I suspect swapping out the modem for one of their Motorola SB5101's to rent, or purchasing my own might solve this.
It shouldn't be necessary to clone my PC's MAC address to the router, should it?
That all looks normal to me. I see no missing default gateway IP address? If you added that override in Windows, remove it. The only think odd I see is that you have BOTH ethernet and wireless adapters working at the same time to the same router. Only one is needed and I would definitely favor the ethernet connection, so disable the wireless adapter. If you want to go wireless after you get this problem solved, that's fine.
No, you do not need a crossover cable, the router will automaitcally handle it, so you can ignore that.
I would definitely reset the WNDR3700 to facotry defaults, just becasue it came out to the box doesn't mean the settings are correct, it might have been previously tested and not reset at the factory. See your manual and follow the reset prodedure and do NOT run the setup afterwards, simply use it. If things work, then log into the router and reset the admin password, wireless security, etc.
I would reset the modem again, but do it like this:
Remove the ethernet cable from the modem.
Press and hold the Reset button on the modem until it reboots.
Let it connect to Comcast and stablize.
Remove the WNDR3700's power cord.
Now connect the WNDR3700's WAN/Internet port to the modem's ethernet port.
Power up the router.
Now test things out. If things are still wonky, go into your connection settongs in Windows and override the DNS servers to 22.214.171.124 and 126.96.36.199 (those are the Comcast DNSSEC servers). Your connections are using your router as a DNS proxy and that may be the issue, which is why I recommended a firmware update earlier.
Did you try disabling IPv6 in the router or in Windows?
While the modem is likely NOT the culprit here, if you are paying rental on this modem, I would replace the modem with your own Motorola SB6120/SB6121 and save yourself $7/mo as long as you no longer have Voice service.
I manually added 192.168.1.1 to my gateways in the network adapter settings of my laptop. I'll remove that.
I disabled the wireless adapter in network settings in Windows 7 on the laptop temporarily while working on this issue.
Couldn't find where to disable IPv6 in the Netgear router, so I unchecked the box by IPv6 in my network adapter settings on my laptop, and rebooted. Made no difference. I didn't actually follow that whole article you linked to, so I didn't verify that it's actually disabled.
I also reset the Netgear router to factory defaults, and still it made no difference. Went into "router status", and "connection status", and hit "release" and "renew" several times, and I have an IP showing under router status, and the DNS servers 188.8.131.52 and 184.108.40.206 are there. But the problem remains. The firmware is already the latest.
Looking at the two ipconfig/all results I posted, I've noticed that the subnet mask when connected direct to the modem is 255.255.252.0, while behind the router it's 255.255.255.0. Could that be a problem?
I'm a friend of the person who holds this account, and I've been trying to coach her through all this via Skype IM. Thanks for your help. A tech should be out today to have a crack at fixing this. I'll try and post the resolution to all this for the benefit of others that might have a similar problem, if possible. I want to know myself, because this has nearly driven me bat sh*t
To disable IPv6 on the router, scroll down the blue menu on the left side of the screen after you log in to the router. You will see an 'IPv6' item. Click on it, and set the Connection Type to Disabled.
The different subnet mask you see when connected to the modem vs the router is normal. Comcast are assigning you an IP address out of a very big network when you connect to the modem directly. When you connect the PC tot he router, you are assigned an IP out of a much smaller network defined on your router, hence the netmask with more bits...
I had her remove the manually added gateway of 192.168.1.1, and then enter 220.127.116.11 and 18.104.22.168 into the DNS section under her network adapter settings, per your suggestion, and viola! All sites load, and our Skype calls are restored! Thanks Barric, we cancelled the tech, and saved the possible $30 tech fee. Thanks Barric, and thanks BruceW for your help It worked fine before with DHCP enabled alone...odd that it would suddenly need to be entered manually. Maybe it has something to do with that DNSSEC roll out.
It does sound like there is something not quite right about the DNS proxy setup in the router such that it's not working well with the Comcast DNSSEC systems. You know it's not a basic DNS issues since your computers are using the same servers as the router and that works fine, so it's limited to the proxy setup somehow. You might keep an eye peeled for a firmware update to that router to address the issue and give it a try when posted. I would also recommend you report this to the manufacturer so they know they have a potential problem effecting a very large Comcast user base.
I had her do the modem reset the way you suggested before manually adding the DNS servers. She unhooked the ethernet cable from the modem, and then pushed the reset button. Hooked the cable back up, powered up the router, and then tried loading her college site. It wouldn't load. Then entered the DNS servers into the network adapter settings, and rebooted the laptop. Then all her sites loaded, and she could make and receive Skype calls again. Maybe, if we had simply rebooted the laptop before adding the DNS servers, it would have worked.
Later she booted up her PC, which connects wirelessly to the router, and all the websites loaded, and she called me on Skype on it, and it all worked. WITHOUT manually adding the DNS servers to the network adapter settings.
Before, we were doing the modem reset and power cycling the router and rebooting the laptop with both ethernet cables connected, per the instructions on Comcast's site.
I had her check the router status tab the previous night, and under Domain Name Server, it was showing 0.0.0.0. So I had her click connection status, and click on the renew and release buttons, and then the router had the 22.214.171.124 and 126.96.36.199 servers showing under router status. Had we just done the power cycles and a reboot, it might have worked then.
Why would unhooking the ethernet cable from the modem make a difference, when the router was unplugged from power while doing the modem reset?
If the problem was a firmware issue related to handling DNS proxy and DNSSEC, then all three routers that have the latest available firmwares have the same problem.
Just glad the issue is resolved, even if we're not entirely sure what fixed it
The only explanation I can come up with is the modem was at fault in some fashion and the resets were not correcting the problem, possibly because the device never lost power if it's getting a trickle of power over ethernet. Power Over Ethernet (PoE) is possible but most consumer devices don't support it unless they are meant to be used in areas with no traditional power. Other than that very vague bit of hand waving, I have no other explanation that fits the observed evidence.
But as long as it's working now, I guess that's all that ultimately matters.