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internet keeps dropping. sb8200 modem all lights turn off except for the top one

acf1
Regular Visitor

internet keeps dropping. sb8200 modem all lights turn off except for the top one

Hi

My internet keeps dropping. sb8200 modem all lights turn off except for the top one. I have to unplug it, wait 10 seconds and replug it in order for the other lights to come back. What is the issue?

 

current status and logs below:

 

Procedure Status Comment
Acquire Downstream Channel 495000000 Hz Locked
Connectivity State OK Operational
Boot State OK Operational
Configuration File OK  
Security Enabled BPI+
DOCSIS Network Access Enabled Allowed

 

Channel ID Lock Status Modulation Frequency Power SNR/MER Corrected Uncorrectables
20 Locked QAM256 495000000 Hz -1.3 dBmV 40.7 dB 0 0
12 Locked QAM256 447000000 Hz -0.4 dBmV 40.9 dB 0 0
13 Locked QAM256 453000000 Hz -0.5 dBmV 40.9 dB 0 0
14 Locked QAM256 459000000 Hz -0.5 dBmV 40.8 dB 0 0
15 Locked QAM256 465000000 Hz -0.7 dBmV 40.8 dB 0 0
16 Locked QAM256 471000000 Hz -0.9 dBmV 40.8 dB 0 0
17 Locked QAM256 477000000 Hz -0.9 dBmV 40.7 dB 0 0
18 Locked QAM256 483000000 Hz -1.2 dBmV 40.6 dB 0 0
19 Locked QAM256 489000000 Hz -1.2 dBmV 40.8 dB 0 0
21 Locked QAM256 507000000 Hz -1.0 dBmV 40.0 dB 0 0
22 Locked QAM256 513000000 Hz -0.8 dBmV 40.8 dB 0 0
23 Locked QAM256 519000000 Hz -0.6 dBmV 40.9 dB 0 0
24 Locked QAM256 525000000 Hz -0.7 dBmV 40.7 dB 0 0
25 Locked QAM256 531000000 Hz -0.7 dBmV 40.7 dB 0 0
26 Locked QAM256 537000000 Hz -0.8 dBmV 40.7 dB 0 0
27 Locked QAM256 543000000 Hz -0.8 dBmV 40.7 dB 0 0
28 Locked QAM256 549000000 Hz -1.1 dBmV 40.6 dB 0 0
29 Locked QAM256 555000000 Hz -0.9 dBmV 40.6 dB 0 0
30 Locked QAM256 561000000 Hz -1.0 dBmV 40.6 dB 0 0
31 Locked QAM256 567000000 Hz -1.2 dBmV 40.4 dB 0 0
32 Locked QAM256 573000000 Hz -0.8 dBmV 40.6 dB 0 0
33 Locked QAM256 579000000 Hz -0.7 dBmV 40.6 dB 0 0
34 Locked QAM256 585000000 Hz -0.5 dBmV 40.7 dB 0 0
35 Locked QAM256 591000000 Hz -0.6 dBmV 40.6 dB 0 0
36 Locked QAM256 597000000 Hz -0.7 dBmV 40.5 dB 0 0
37 Locked QAM256 603000000 Hz -0.9 dBmV 40.2 dB 0 0
38 Locked QAM256 609000000 Hz -0.8 dBmV 40.5 dB 0 0
39 Locked QAM256 615000000 Hz -0.9 dBmV 40.5 dB 0 0
40 Locked QAM256 621000000 Hz -0.7 dBmV 40.4 dB 0 0
41 Locked QAM256 627000000 Hz -0.8 dBmV 40.4 dB 0 0
42 Locked QAM256 633000000 Hz -1.1 dBmV 40.3 dB 0 0
48 Locked Other 688000000 Hz -0.6 dBmV 38.8 dB 181267398

0

 

 

 

 

 

Channel Channel ID Lock Status US Channel Type Frequency Width Power
1 1 Locked SC-QAM Upstream 17300000 Hz 6400000 Hz 44.0 dBmV
2 4 Locked SC-QAM Upstream 36700000 Hz 6400000 Hz 43.0 dBmV
3 3 Locked SC-QAM Upstream 30300000 Hz 6400000 Hz 43.0 dBmV
4 2 Locked SC-QAM Upstream 23700000 Hz 6400000 Hz 43.0 dBmV
5 5 Locked SC-QAM Upstream 41200000 Hz 1600000 Hz 44.0 dBmV

 

 

05/26/2020 00:59 67061600 6 "DS profile assignment change. DS Chan ID: 32; Previous Profile: ; New Profile: 1 2 3.;CM-MAC=14:c0:3e:01:cc:f1;CMTS-MAC=00:01:5c:65:14:7f;CM-QOS=1.1;CM-VER=3.1;"
01/01/1970 00:00 2436694066 6 "Honoring MDD; IP provisioning mode = IPv6"
01/01/1970 00:00 84000100 3 "SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=14:c0:3e:01:cc:f1;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.1;CM-VER=3.1;"
01/01/1970 00:00 82000200 3 "No Ranging Response received - T3 time-out;CM-MAC=14:c0:3e:01:cc:f1;CMTS-MAC=00:01:5c:65:14:7f;CM-QOS=1.1;CM-VER=3.1;"
01/01/1970 00:00 84000100 3 "SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=14:c0:3e:01:cc:f1;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.1;CM-VER=3.1;"
01/01/1970 00:00 82000200 3 "No Ranging Response received - T3 time-out;CM-MAC=14:c0:3e:01:cc:f1;CMTS-MAC=00:01:5c:65:14:7f;CM-QOS=1.1;CM-VER=3.1;"
01/01/1970 00:00 84000100 3 "SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=14:c0:3e:01:cc:f1;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.1;CM-VER=3.1;"
05/25/2020 08:44 82000200 3 "No Ranging Response received - T3 time-out;CM-MAC=14:c0:3e:01:cc:f1;CMTS-MAC=00:01:5c:65:14:7f;CM-QOS=1.1;CM-VER=3.1;"
05/25/2020 08:44 84000500 3 "SYNC Timing Synchronization failure - Loss of Sync;CM-MAC=14:c0:3e:01:cc:f1;CMTS-MAC=00:01:5c:65:14:7f;CM-QOS=1.1;CM-VER=3.1;"
01/01/1970 00:00 82000200 3 "No Ranging Response received - T3 time-out;CM-MAC=14:c0:3e:01:cc:f1;CMTS-MAC=00:01:5c:65:14:7f;CM-QOS=1.1;CM-VER=3.1;"
01/01/1970 00:00 84000100 3 "SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=14:c0:3e:01:cc:f1;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.1;CM-VER=3.1;"
01/01/1970 00:00 82000200 3 "No Ranging Response received - T3 time-out;CM-MAC=14:c0:3e:01:cc:f1;CMTS-MAC=00:01:5c:65:14:7f;CM-QOS=1.1;CM-VER=3.1;"
01/01/1970 00:00 84000100 3 "SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=14:c0:3e:01:cc:f1;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.1;CM-VER=3.1;"
05/25/2020 06:44 82000200 3 "No Ranging Response received - T3 time-out;CM-MAC=14:c0:3e:01:cc:f1;CMTS-MAC=00:01:5c:65:14:7f;CM-QOS=1.1;CM-VER=3.1;"
05/25/2020 06:44 84000500 3 "SYNC Timing Synchronization failure - Loss of Sync;CM-MAC=14:c0:3e:01:cc:f1;CMTS-MAC=00:01:5c:65:14:7f;CM-QOS=1.1;CM-VER=3.1;"
01/01/1970 00:00 82000200 3 "No Ranging Response received - T3 time-out;CM-MAC=14:c0:3e:01:cc:f1;CMTS-MAC=00:01:5c:65:14:7f;CM-QOS=1.1;CM-VER=3.1;"
01/01/1970 00:00 84000100 3 "SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=14:c0:3e:01:cc:f1;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.1;CM-VER=3.1;"
05/16/2020 06:36 82000500 3 "Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=14:c0:3e:01:cc:f1;CMTS-MAC=00:01:5c:65:14:7f;CM-QOS=1.1;CM-VER=3.1;"
EG
Expert

Re: internet keeps dropping. sb8200 modem all lights turn off except for the top one

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 intermittent noise ingressing 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 !



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ComcastAmira
Official Employee

Re: internet keeps dropping. sb8200 modem all lights turn off except for the top one

Hello @acf1, thanks for reaching out to our Digital Care Team through our Forums page. I'm sorry to hear about the connection issues you have been experiencing. I can definitely see how inconvenient and frustrating that must be especially during these troubling times. I would love to assist you and further look into this on my end. Can you please send me a private message including your first and last name as it appears on the account? 

 

To send me a Private Message, please click my name “ComcastAmira” and click “send a message". 


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Official Employees are from multiple teams within Comcast: CARE, Product, Leadership. We ask that you post publicly so people with similar questions may benefit from the conversation.
Was your question answered? Mark the post as Best Answer!