For 2 months now I have been having problems with loosing my internet connection. I have RoadRunner and a Motorola SURFboard SB5120 modem with an attached wireless router and 2 hardwired pc's. When I loose connectivity all lights on the modem are normal. No response from a ping of a web address or an ip address from either the pc or the router, I've tried pinging both my gateway and dns servers ip address. When the problem occurs I also cannot navigate to 192.168.100.1 nor can I ping that address from the router. I also cannot get an ip address from the modem using the routers screen to do a DHCP renew. I ran for a while with a pc attached directly to the modem and when the hangup occurred I cannot renew the ip address. I'm on my 2nd modem and even though it failed the same way when I direct connected it, I changed the router. Doing a power cycle of the modem always fixes the problem. The problem also seems to vanish on it's own if you leave it for a few minutes and try again. The RJ45 cable is also a different one between both routers. It's hard to believe that I've gotten 2 modems with the same problem but I can't for the life of me figure out what to change next. The modem will return an ip address without the cable connected so I can't imagine that the problem is from the cable out. I've also had Roadrunner out here this past Thursday and they changed a few of the cable connections going to the modem but said that everything was fine with the signal. Anyone have any ideas on what to do next.
What do you mean by try again? Try to renew the ip address again?
Both routers? Please explain. The description above mentioned one wireless router?
Well, it's important to realize that the cable modem is designed to give a termporary IP address out if it doesn't have sync to a head end, but when you are sync'd to a head end, it's actually the provider's DHCP server doling out the IP's I believe, and not the cable modem itself.
You could have an intermittent cable signal issue.
Post your upstream and down stream signal levels as well as SNR from http://192.168.1.100/ and are there any entries of interest in the logs from that page? Such as SYNC loss, etc?
AFter the cable comes into the house, what is the routing of the signal on its way to your modem (splitters, etc).
Yes, renew the address. Or if I've never gone into the router and released it, then I mean try and ping or navigate to a web page from my pc.
I mentioned that I changed routers to eliminate them as the problem and just wanted to clarify that when I attached the new router I used it's ethernet cable.
Yes the ip address must come from beyond the modem because if I disconnect the cable from the modem and release and renew the ip address in the router it comes up with something like 192.168.100.something, I can't quite remember. But with the cable hooked up and everything running properly it's
70.127.151.160.
The motorola modems downstream signal to noise was 38 dB and power level was -2 dBmV. Upstream power level was 42 dBmv. Since I posted this info I had since went a got yet another cable modem. Unfortunately the one I got is called a WEBstar by Scientific Atlanta and when I navigate to it at
192.128.100.1 I only have the following System screen available, which just lists Transmit Power Level at 45.5 dBmV and Receive Power Level at -4.9 dBmV. None of the other features screens are available, when I click on them it states the following:
This feature is not enabled. This feature has not been enabled in your cable modem.
Please contact your data services provider for more information about this feature and its availability on the network.
I don't know from that comment if there is something Bright House Networks could have me do to the modem to enable those features, it sounds like it but they probably don't want users messing with it. This, the 3rd modem hung about an hour after installing it but for the last 6 or 7 hours it has been just fine. To backtrack just a little: After the cable guy left on Thursday it ran fine the rest of the night. On Friday we had the same problem so I went to the Bright House offfice and got a replacement modem, that was the 2nd. It failed and I posted this msg in the newsgroup. Then today again, I went and got the 3rd modem. It might run a day or 2 just fine or it might fail, run an hour and fail again. Every time it fails, all I do is recycle power on it and everything is fine. I do not have to reset the router and do not loose my ip addresses in the pc's and I don't believe both my routers cause the same problem. I also can't believe something in one of my pc's is causing the cable modem to hang. It's as if some signal comes down the cable line and hangs the modem.
For lack of anything to do I think I will start logging the times it hangs and see how long it takes to clear on it's own. If it would stay hung long enough I could probably get Bright House Networks on the line to look at it. We've had RoadRunner for a long, long time. Well over ten years and during that time had 1 cable modem, a cream colored Motorola and as long as the cable light was on we never had a problem. Max speed with it was 2.5mbps. About 2 years ago they called, set up an appointment to change out what they called the legacy cable modems. My speed went to 5mbps instantly and shortly after close to 7. It's been fine up until just a few months ago when all this started.
My cable comes to the house and attaches to a 3 way splitter. From there one goes directly to my cable modem, the 2nd to my living room (split there for tv, dvd recorder) and the 3rd to the family room ( split 4 ways for 2 tv's and 2 pc tv cards).
I concur that you're probably dealing with a cable system or signal issue.
I agree.
Do get them on the horn while yer hung up. At least you can then tell if their network can still talk to the cable modem. If they can't, then you know the problem is with the cable modem, signal issues or cable network.
For s**ts and giggles, I would try running with the splitter removed. Move the cable modem downstairs with the wireless router if needed, or just put a female to female f connector in place of the splitter. I'm curious if that cleans things up.
If it does, get the cable guys out there, report the results of your extended experiment and get them to get your cable modem feed from directional coupler instead of that standard splitter. Cable modem gets the low loss output of the DC, TV's get fed by the tap end (possibly requiring an amplifier for the TV's benefit).
I've made it a whole day and a half with not incidents of not being able to get on the internet. I've been running a program called "LinkMonitor" and pinging Yahoo's ip address every 15 seconds for around 3 weeks. Lately the cable light started going out when we would lose connectivity but not always. Bright House could never find anything wrong with the cable because it was always working just fine when they came to check. While I don't know exactly what part fixed it I do know that it was one of the parts they just change a few days ago. My cable comes into a box outside the house. It goes through a male to male junctions that is attached to a ground wire. From the junction it goes to a 3 way splitter. They replaced the splitter, the male to male junction and all 6 connectors on the cables that interconnect it all and so far it hasn't missed a beat. Thanks to everyone for their suggestions.
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