Anon57998611's profile

Contributor

 • 

27 Messages

Friday, December 18th, 2020 5:00 AM

Closed

Internet consistently dropping out

I am hoping someone can help me.  I have a Cisco DPC3941T gateway.  I have the 600 Mbps level of service.  Full disclosure, I also have a Synology router.

 

I am remote working, and I have two who are remote schooling here.  Due to the nature of work I do, I am using a desktop connected via an ethernet cable to the Cisco gateway for my video meetings.  (Again, more full disclosure - one student connected to Synology route via ethernet, one student connecting via wifi.)  I am also using a laptop connected to wifi (although what I am doing on laptop does not require internet connection.)

 

We are consistently losing the internet.  in the course of my four-hour meeting yesterday, I lost it at least six times, which requires me to log all the way back into the meeting and disrupt everything.   Of course, the top-level boss was running this meeting. 

We also consistently lose internet during the course of the day -- using an Alexa, we'll be listening to the radio (when no one is online yet), the station will drop, and we get a "I'm having trouble understanding now.  Try again later."

 

We can rule out the Synology router as the issue as I am connected directly to the gateway.  

 

When this happens and I look at the gateway, all of the lights on the front remain lit.

 

I have power cycled the gateway (multiple times yesterday), checked to make sure all the connections were tight and that there were no visual problems with the ethernet cables. 

 

I tried chatting and finally received a call from an agent yesterday who told me that they would send a refresh signal to my modem, and over my objections, told me that since I had internet, I had no problems and terminated the call.

 

The continuously dropping internet is an enormous problem -- one that is now affecting my job -- and I am posting in the hopes someone give me ideas on how to narrow my problem and have proof so I can get someone at Comcast to actually listen to me and help me fix this.  (Frankly, I really believe it's an issue with the cable that comes into the house but I don't know how to prove that.)  I'm relatively tech savvy, but I've hit a wall and need and would appreciate any help.

 

ETA:  And of course can't get thru chat or call back to actually speak to someone for assistance.  

 

Thank you.  

Expert

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110K Messages

4 years ago

Can't see your pics. Since you are a new poster, they need to be approved by a Forum Admin. That could take some time. In the interim, you could try hosting them at one of those free third-party pic hosting sites like Imgur or Photobucket and post the link to them here.


Or copy all of the text of the status page and paste it into the body of your next post here.

Contributor

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27 Messages

4 years ago

Here's what I get from the gateway.  Anything else I should add?

Anon57998611_0-1608312000760.png

 

Anon57998611_1-1608312037922.png

 

Anon57998611_2-1608312211378.png

 

 

Contributor

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27 Messages

4 years ago

Error.  I'm not finding the SNR ratio right now. 

Unerrored CodewordsCorrectable CodewordsUncorrectable Codewords

1502300491
1498042449
1447507299
1447508337
1497993327
1498015805
1497935896
1497936167
1497900433
1447517470
1447522828
1497879045
1497877628
1497968277
1497878827
1447532356
1447533066
1497873317
1447468332
1497879513
1497875231
1447479594
1447531733
1447537254
0
0
16
15
17
1
0
0
1
0
0
1
0
7
1
0
0
0
0
1
0
0
8
1
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
1
0
0
0
0
0
0

Expert

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110K Messages

4 years ago

Start with the modem's signal stats. Perhaps they already are, or they are close to being out of spec and intermittently they go completely of spec. 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.


Expert

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110K Messages

4 years ago

Disregard my last reply. I see now that you posted them.

 

Even though the signal stats looked o/k at that snapshot in time, the error log entries confirm that something is going on. Perhaps there is noise ingress into the line(s) somewhere.

 

There are other signal stat figures that can't be read by the modem. They are the "Upstream Rx Power" (Upstream Receive Power Level), the "Upstream SNR Ch." (Upstream Signal To Noise Ratio), and the "Upstream ICFR" (In Channel Frequency Response). These are as equally important in diagnosing connectivity issues as are the modem's stats.


I'm going to escalate your issue to the Comcast corporate employees that are available to these boards. They can check the CMTS (Cable Modem Termination System) for any real time degradation and / or error reports, see your node / cable plant and modem health, and see whether or not everything is in the green zone. They can also see a history plot for the modem and poll for those upstream receive signal stats.

You should get a reply here in your topic. Good luck !

Contributor

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27 Messages

4 years ago

Thank you so very much for your help.  This has been frustrating!  

Contributor

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27 Messages

4 years ago

Okay.  let me figure out how to do that.  There's a lot there.

Contributor

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27 Messages

4 years ago

Thank you -- but it's not the modem I'm connected to, it's the gateway.  

 

Expert

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110K Messages

4 years ago

The SNR values are there with the downstream channels, and they are all good. As is everything else. 

 

Are there any error log entries being shown ? If so, please also post them in their entirety.

Contributor

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27 Messages

4 years ago

Sorry for all the posts.  This is some of my event log for yesterday.

[Dhcpc][1854]: mta0 got new IP 21.162.234.1232020/12/18 03:03:43Notice
[Dhcpc][25141]: erouter0 got new IP 71.59.100.402020/12/17 14:18:47Notice
[Dhcpc][20482]: mta0 got new IP 21.162.234.1232020/12/17 14:15:05Notice
[Dhcpc][6877]: mta0 got new IP 21.162.234.1232020/12/17 13:54:51Notice
[Dhcpc][7081]: erouter0 got new IP 71.59.100.402020/12/17 13:54:14Notice
[Docsis][974]: No Ranging Response received - T3 time-out2020/12/17 13:35:20Warning
[Docsis][974]: No Ranging Response received - T3 time-out2020/12/17 13:35:20Warning
[Docsis][974]: No Ranging Response received - T3 time-out2020/12/17 13:35:19Warning
[Docsis][974]: No Ranging Response received - T3 time-out2020/12/17 13:35:19Warning
[Docsis][974]: Unicast Maintenance Ranging attempted - No response - Retries exhausted2020/12/17 12:27:57Critical
[Docsis][974]: Ranging Request Retries exhausted2020/12/17 12:27:57Critical
[Docsis][974]: No Ranging Response received - T3 time-out2020/12/17 12:27:32Warning
[Docsis][974]: No Ranging Response received - T3 time-out2020/12/17 12:27:31Warning
[Docsis][974]: No Ranging Response received - T3 time-out2020/12/17 12:27:30Warning
[Docsis][974]: No Ranging Response received - T3 time-out2020/12/17 12:27:29Warning
[Docsis][974]: No Ranging Response received - T3 time-out2020/12/17 12:27:27Warning
[Docsis][974]: No Ranging Response received - T3 time-out2020/12/17 12:27:26Warning
[Docsis][974]: No Ranging Response received - T3 time-out2020/12/17 12:27:25Warning
[Docsis][974]: No Ranging Response received - T3 time-out2020/12/17 12:27:24Warning
[Docsis][974]: No Ranging Response received - T3 time-out2020/12/17 12:27:22Warning

Expert

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110K Messages

4 years ago

Click on whichever blue colored link that gives you access to the user interface pages and look for that requested info.

Contributor

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27 Messages

4 years ago

Downstream:

ndexLock StatusFrequencySNRPower LevelModulation

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
Locked
Locked
Locked
Locked
Locked
Locked
Locked
Locked
Locked
Locked
Locked
Locked
Locked
Locked
Locked
Locked
Locked
Locked
Locked
Locked
Locked
Locked
Locked
Locked
549 MHz
555 MHz
561 MHz
567 MHz
573 MHz
579 MHz
585 MHz
591 MHz
597 MHz
603 MHz
609 MHz
615 MHz
621 MHz
627 MHz
633 MHz
639 MHz
645 MHz
651 MHz
657 MHz
663 MHz
669 MHz
675 MHz
681 MHz
687 MHz
40.366 dB
40.366 dB
40.946 dB
40.946 dB
40.366 dB
40.366 dB
40.366 dB
40.366 dB
40.366 dB
40.366 dB
40.366 dB
40.366 dB
40.366 dB
38.983 dB
38.983 dB
38.983 dB
40.946 dB
38.983 dB
38.983 dB
38.983 dB
38.983 dB
38.983 dB
38.605 dB
38.983 dB
0.800 dBmV
0.800 dBmV
0.900 dBmV
0.900 dBmV
0.600 dBmV
0.400 dBmV
0.300 dBmV
0.200 dBmV
0.000 dBmV
-0.200 dBmV
-0.600 dBmV
-0.700 dBmV
-1.000 dBmV
-1.200 dBmV
-1.600 dBmV
-1.500 dBmV
-1.300 dBmV
-1.400 dBmV
-1.700 dBmV
-1.900 dBmV
-1.900 dBmV
-2.100 dBmV
-2.400 dBmV
-2.600 dBmV
256 QAM
256 QAM
256 QAM
256 QAM
256 QAM
256 QAM
256 QAM
256 QAM
256 QAM
256 QAM
256 QAM
256 QAM
256 QAM
256 QAM
256 QAM
256 QAM
256 QAM
256 QAM
256 QAM
256 QAM
256 QAM
256 QAM
256 QAM
2

Contributor

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27 Messages

4 years ago

Upstream:

IndexLock StatusFrequencySymbol RatePower LevelModulationChannel Type

Upstream
Channel Bonding Value
1
2
3
4
Locked
Locked
Locked
Locked
30 MHz
17 MHz
23 MHz
36 MHz
5120 KSym/sec
5120 KSym/sec
5120 KSym/sec
5120 KSym/sec
38.500 dBmV
36.750 dBmV
37.250 dBmV
38.500 dBmV
64 QAM
64 QAM
64 QAM
64 QAM
ATDMA
ATDMA
ATDMA
ATDMA

Expert

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110K Messages

4 years ago

My pleasure ! Issue escalated.

Contributor

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27 Messages

4 years ago

I am still having the issue on and off, although not as bad as the day I posted.  I haven't heard back from anyone yet.

 

As an aside, maybe I'm missing it -- is there a way to change my forum name?  I can't see how to do it.

Thanks!

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