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Netgear Nighthawk X4S AC3200 Wifi Cable Modem Router (Model C7800) Internet randomly drops
Netgear Nighthawk X4S AC3200 Wifi Cable Modem Router (C7800-100NAS)
Model: C7800
Firmware Version: V3.01.36
I've recently purchased this netgear cable modem router. I've activated it with Xfinity and successfully have connected to the internet. I have the router placed out in the living room with no obstructions. But once in a while the internet would randomly drop (it'll stop working on all devices regardless if it's an android phone, iphone, windows 10 pc, xbox, etc). Any device connected to router via wifi or ethernet all say they are connected to the router, but "no internet". My firmware is the latest (I've already checked the Netgear download center). I also have the optimal MTU size setup. Unplugging the router for a couple minutes and replugging does solve this issue although not permanently. It's quite annoying that I have to do this every couple hours to couple days. Is there a solution to stop the random drops?
12 Replies
Hello kurosic
Have you checked the modem logs to see if any timeouts are happening?
DarrenM
Okay. I just checked right now. I can definitely see in the event log that there has been multiple timeouts. What does this mean and how do I fix it?
The event log also mentions "Timing Synchronization failure" and "No Ranging Response received".
Please post full Event log and network log here.
I have a Nighthawk C7800 and am having the exact same problem. Ive had Comcast come out and I have spoken to them on the phone countless times - but they havent been able to permanently fix the issue. Were you able to resolve your problem?
My post regarding dropping internet subsided somewhat, but lately I have been experiencing DOS ATTACKs and I've had my Amazon Echo (Alexa) drop as well as my porch Security Camera. The other day, my Netgear WiFi Extender dropped from the Internet and I had to reboot the AC3200 to get everthing to work. Numerous DOS Attacks over the past couple days regarding "UDP Scan" "ECHO CHAR GEN" AND "SYNC FLOOD". Searching the IP addresses (using "Who Is" on Google) gives me various countries (although they could be fake ones). Somewhat concerned about these "Denial of Service" DOS Attacks. Are Netgear Nighthawk Modems under Cyber Attack? What can be done to stop them?
FROM IP: COUNTRY 1/17/2018 80.82.77.33 SEYCHELLES 178.223.136.143 SERBIA 185.94.111.1 RUSSIAN FEDERATION 1/18/2018 113.96.223.207 CHINA 184.105.139.101 USA - DENVER, CO HURRICANE ELECTRIC 185.13.36.43 FRANCE
