[juusan]

I'm having issues with my comcast high speed internet and airport base station. everything was working great up until two weeks ago, and it all went to hell. when I connect the base station to the cable modem, I get no internet - the cable modem won't assign the router an IP. when I try to renew the IP address, it times out. no internet for any of the devices on the network... cabled or otherwise.

but if I connect my ibook directly to the cable modem, I connect to the internet just fine. the modem gives the laptop an IP without a problem.

I've tried THREE different wireless routers - the base station, a linksys, and a d-link. yes, I've also tried replacing the cat5 cable.

eight calls to comcast later, and they still have no idea what the problem is. one guy tried to tell me that all of my airport cards (four on my network total) fried at the same time. riiiiiight.

anyone have any idea what the problem might be? searching google yields a lot of people with the same problem but no answers. everything was working great, and then pfffft! a friend in the same city is having a similar problem, but comcast won't cop to any issue on their side.

[rjt1000]

Hi,

I'm using Comcast (in another city) and an airport extreme base station without any problem.

I would do a hardware reset on the base station (hold in the reset button for 30 seconds or so), that will reset all to factory default (you will lose all your settings so make note of them first if needed).

Then unplug the cable modem and airport extreme base station from power source and turn off your computer. Connect the cable modem and base station with a known good ethernet cable, but disconnect everything else from the network.

Power up the cable modem first, wait a minute, then power up the base station. After another minute, power up your computer and look for the airport network with the default name.

If you are able to connect to the wireless signal, open the network system preferences to see if you are getting an ip address assigned and whether you are connected to the internet.

If you are still not getting an ip address assigned, plug an ethernet cable into the airport extreme LAN port and connect that to your iBook to see if the airport base station will assign an address this way.

Its hard to think of an isp based issue since the cable modem will assign an address to your iBook when connected directly.

Good luck,

rjt1000

[juusan]

I've been following these steps for days now, to no avail. :/ thanks though!

it's weird... I get complete wireless connectivity through the router, but no internet access. when I check the router's status panel, there's all zeros in the ip address assigned from the modem... but when I plug my ibook directly into the cable modem, I get an IP with no problem. farking frustrating.

THREE DIFFERENT ROUTERS!!!!!

[ghporter]

Turn off the modem. Turn off the router. Plug the router into the modem. Turn ON the modem and wait a timed 3 minutes (to allow it to completely boot and set itself up). Turn ON the router and wait a timed 3 minutes (again for boot and setup). This should allow the modem to properly "see" the router and establish the connection.

Give it a try. All you have to lose is a few minutes boredom.

[rjt1000]

Another thought or two in case the above hasnt worked and you havent tried these yet:

1. in the network system prefs select show: airport from the popup, click on TCP/IP and double check that you have "using DHCP" selected.

2. if the iBook is the only wireless computer on the network, try to borrow a friends wi-fi enabled laptop and see if the connection problem persists.

3. check software update to see if there are any updates available for your iBook system or for your airport admin utilities.

Good luck,

rjt1000

[workhard]

Hi,

I had the identical problem with my Airport network. No access through the Airport, but no problems through the direct ethernet connection to the cable modem.

After resetting ALL of my base stations, which did not help, I called Comcast tech support.

These are the steps.

1. Connect Airport to cable modem normally - no internet access, only internal distributed IP address.

2. Connect laptop to LAN port of Airport - no internet access.

3. Use Network Utility to ping out to Google's IP address (although any should do). Try 64.233.161.147. Was able to ping out!!

4. Open up Safari, enter same IP address, and there it was, Google.

5. Went back and entered two DNS servers closest to me in DNS server box in Airport Admin Utility:

Comcast (pick the nearest!)
68.87.66.196 Comcast (national) Primary DNS Server.
68.87.64.196 Comcast Secondary DNS Server.
68.57.32.5 (Virginia)
68.57.32.6 (Virginia)
216.148.227.68 (Denver, Colorado)
204.127.202.4 (Denver, Colorado)
68.42.244.5 (Taylor, Michigan)
68.42.244.6 (Taylor, Michigan)
68.62.160.5 (Huntsville, Alabama)
68.62.160.6 (Huntsville, Alabama)
68.87.96.3 (Pennsylvania)
68.87.96.4 (Pennsylvania)

6. Restarted Airport, and now I have access again. A little slow, but working nevertheless.

7. This site has a listing of many of the DNS servers. You might want to do your own search, and use some other, non-Comcast DNS server.
http://www.portforward.com/networking/dns.htm


I think Comcast's DNS servers were down, but no one in tech support would say that.

Anyway, worked for me. Hope this helps.


Tung Nguyen

[ghporter]

Tung, that's great stuff! Thanks for posting it. DNS servers MUST be reliable--and it looks like Comcast is having problems.