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Constant Wifi Drops CGM4140COM, firewall logs show IPV6 Forward & Input drops

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Constant Wifi Drops CGM4140COM, firewall logs show IPV6 Forward & Input drops

New Xfinity internet customer, have had ongoing issues since day 1 this month.  Xfinity tech replaced outdoor wiring, 2nd tech replaced modem with CGM4140COM the latest.  Troubleshooting mode in the Gateway shows firewall logs have hundreds of FORWARD and INPUT drops.  Is there a solution?  The only fix at our end is to disconnect the device (PC, Mac, phone, tablet) from wifi and reconnect.  This is not workable, lose connection multiple times in a few minutes, all day long.  Tech said it could be interference from "anything" like microwave etc but based on all the similar issues I've seen posted it's something to do with the router itself.

Expert

Re: Constant Wifi Drops CGM4140COM, firewall logs show IPV6 Forward & Input drops

For a test, does a computer hardwired directly to the gateway device with an ethernet cable have the same problem ?



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Frequent Visitor

Re: Constant Wifi Drops CGM4140COM, firewall logs show IPV6 Forward & Input drops

Yes. I only have one older laptop with an Ethernet port (the rest are newer laptops with no LAN port) so I just hooked that one up 10 min ago and already see drops.  This is today. 

FW.IPv6 FORWARD drop , 301 Attempts, 2019/5/29 10:52:08 Firewall Blocked  
FW.LAN2SELF DROP , 6 Attempts, 2019/5/28 19:58:01 Firewall Blocked
Expert

Re: Constant Wifi Drops CGM4140COM, firewall logs show IPV6 Forward & Input drops

Are you actually experiencing complete internet connection drops to all sites or are you just focusing on those firewall log entries ?



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Re: Constant Wifi Drops CGM4140COM, firewall logs show IPV6 Forward & Input drops

We are experiencing actual drops to the devices.  The only reason I checked the logs at all was based on perusing the internet for a solution to the constant interruptions of service.  We have to turn off the wifi on the device and turn it back on to reconnect.  This is across multiple platforms and devices.

Expert

Re: Constant Wifi Drops CGM4140COM, firewall logs show IPV6 Forward & Input drops

What do the modem's signal stats look like ? Try getting them here http://192.168.100.1 or here http://10.0.0.1

Please post the *Downstream Power Level*, the *Upstream Power Level*, and the *SNR* (Signal to Noise Ratio) numbers.




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Re: Constant Wifi Drops CGM4140COM, firewall logs show IPV6 Forward & Input drops

My connectons aren't optimal strength either.  In order from top they are:

Windows Laptop on 5G

Modem/Arcadyan network monitor 5G

Mac book on 5G

iPad (older) on 2.4 G

Windows PC laptop on 5G

Brother printer on 2.4 G

Older Windows latop on Ethernet direct

 

All devices are in the next room over from modem and Xfinity tech mapped the house, they have good signal.  So why not better than 80 on 5G

Connections.JPG
Frequent Visitor

Re: Constant Wifi Drops CGM4140COM, firewall logs show IPV6 Forward & Input drops

Here are those levels

Downstream etc.JPG
Expert

Re: Constant Wifi Drops CGM4140COM, firewall logs show IPV6 Forward & Input drops

Can you please post the balance of the downstream channels.

 

Some tips for improving WiFi performance;


http://corporate.comcast.com/comcast-voices/10-ways-you-might-be-killing-your-home-wi-fi-signal

 

http://forums.xfinity.com/t5/Your-Home-Network/Improve-Your-Wireless-Gateway-Home-Network/td-p/26276...

 

There are other options. Google for WiFi repeaters / range extenders, WiFi mesh systems / pods, powerline ethernet adapters, MoCA adapters.



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Re: Constant Wifi Drops CGM4140COM, firewall logs show IPV6 Forward & Input drops

Why was this moved?

Frequent Visitor

Re: Constant Wifi Drops CGM4140COM, firewall logs show IPV6 Forward & Input drops

None of these apply.  An expert tech has mapped the inside of the house.  The modem is central and not close to anything emitting a signal.  The devices getting dropped are within a few feeet and clear line of the modem.  My old AT&T DSL never had these issues with the modem in the same place.   This is specific to the new equipment and/or provider.

downstream2.JPG
Expert

Re: Constant Wifi Drops CGM4140COM, firewall logs show IPV6 Forward & Input drops


@KR9 wrote:

Why was this moved?


It wasn't. Someone else's post that was stepping on your thread here was moved.



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Expert

Re: Constant Wifi Drops CGM4140COM, firewall logs show IPV6 Forward & Input drops

You didn't post the balance of the channels... Anyway, good luck with this ! Smiley Happy



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Re: Constant Wifi Drops CGM4140COM, firewall logs show IPV6 Forward & Input drops

I thought this was what you asked for whiich I did post above.  Is this it?

downstream2.JPG
Expert

Re: Constant Wifi Drops CGM4140COM, firewall logs show IPV6 Forward & Input drops

It's all good. The modem's RF stats are in spec.



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Re: Constant Wifi Drops CGM4140COM, firewall logs show IPV6 Forward & Input drops

Thank you EG. 

For anyone, yes modem specs look OK; Xfinity has been monitoring at their end, signal from street to modem looks good. 

 

Nonetheless, Wifi signal doesn't maintain and is lost frequently on multiple devices on multiple platforms even when in close proximity to the modem/router including in the same room.  There is no telephone line  or radio frequence telephpones in the house beside personal cell phone.

Frequent Visitor

Re: Constant Wifi Drops CGM4140COM, firewall logs show IPV6 Forward & Input drops

Expert tech came by and turned off the Firewall completely on IPV6 and IPV4 as a troubleshooter step.  I also turned off the one electronic device in the same room as the modem.  Yet the logs show the Forward drops continuing, number has gone up by 200 in the last 30 min alone. LAN however has had no more since plugged in.  It is just wireless.

Firewall drops continue.JPG
Frequent Visitor

Re: Unbelievable internet slow speed

I  have having terrible wifi issues on this same model brand new modem as well.  Constant loss over and over again even a few feet away.  Xfinity says delivery of signal to modem is OK, but from modem/router to wireless devices is the problem.  Not resolved, I have an active thread today at https://forums.xfinity.com/t5/Your-Home-Network/Constant-Wifi-Drops-CGM4140COM-firewall-logs-show-IP... .   Under Troubleshooting/Logs the Firewall log shows Input Drops and Forward Drops, now continuing even with the Firewall disabled completely by a Tech.   No solution so far and Comcast suggests I pay for extenders.  I think I will have to buy my own modem/router vs this rented one that clearly has issues.  My old AT&T modem/router in the same spot in the house had zero issues.

Expert

Re: Constant Wifi Drops CGM4140COM, firewall logs show IPV6 Forward & Input drops

"Expert" is a relative term... Have you tried having the gateway swapped out for another ?



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Frequent Visitor

Re: Constant Wifi Drops CGM4140COM, firewall logs show IPV6 Forward & Input drops

Well, the XB6 gateway is a swapped out modem for the prior one whiich was whatever is currently provisioned with 150mbps.  Prior to that we had speed issues; with this gateway, speed is now more consistent but the  connecton to the router has gone from bad to worse.

Silver Problem Solver

Re: Constant Wifi Drops CGM4140COM, firewall logs show IPV6 Forward & Input drops

FYI, I have the same drops in my XB6 and it doesn't seem to be causing me any issues.


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Re: Constant Wifi Drops CGM4140COM, firewall logs show IPV6 Forward & Input drops

Can anyone suggest why older routers (both AT&T for Uverse, and prior Xfinity routers  (Arris, Netgear) would have held the wifi connections better, in the same spot in the house?