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Netgear Nighthawk CM1100 DOCSIS 3.1 Cable Modem
I got the cm1100 cable modem docsis 3.1 from amazon and it works but there wierd thing happen regulary the internet stop working then for some minutes reboot it self back on as I keep seeing the mode...
patricia2626 wrote:I got the cm1100 cable modem docsis 3.1 from amazon and it works but there wierd thing happen regulary the internet stop working then for some minutes reboot it self back on as I keep seeing the modem i got green lights front boot to one by one until reaches the last bottom light then I get internet back as It get annoing some times I was random times once as some time it 2-5 times per day.
Is there problem defetive in the modem or is it comcast problem as I do use a nighthawk r8000 to get wifi internet.
More info helps.You need to figure out if its truly a modem problem or if its the R8000 problem with talking to the modem.
1. If it happens 2-5x a day try directly connecting a computer to the modem and taking the router out of the equation. Does the problem still happen?
2. If you log into the modem, how does your connections page look? Take screens snips of it and link to them here. Don't post pictures as a moderator has to approve them and can take a while.
3. Do the same with your logs.
4. How do you have the cm1100 wired? it does have 2 ports but you can't use both unless you're using them as port aggregation (your provider must support this feature through firmware updates)
You have a lot of uncorrectables plus the dynamic range window violation. dynamic range window violation is usually when you're power difference exceeds 12dB. Most usually there's a fault in the line with either a cable, connector, amplifier, etc.
Here's what I'd do for troubleshooting.
1. remove any splitters from the line. (you're power might be a bit to high but its for testing purposes)
2. check all your cables. Make sure the connectors are all good and inspect the cables. I've had a small nick in one give me errors that weren't resolved until I replaced the cable.
3. Hook the modem up directly where it comes into the house. Try not to use any splitters. Just direct connection.
How is the cm1100 wired? CM1100--->Router--Computer? Hopefully. make sure you're not using the 2nd port on the cm1100
I dont use spiltters or adapters there both next to each other and not sure about the cables having problems I got the internet cables from amazon cat6a
https://www.amazon.com/gp/product/B00HEM5MZU/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1
Your coax cables. check these You strength coming in and snr look good but your getting the dynamic range window violation in your logs which usually means you're getting >12dB difference in strengths. Maybe something is spiking/erroring. Again, check your coaxial cables for damage, bad ends, cheap cables, water damage, etc.