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Intermittent Network Shutdown

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Intermittent Network Shutdown

Hello,

 

We have been having issues with our internet connection intermittenly shutting down, requiring a restart to re-obtain internet access. We have the gigabit plan, use a NETGEAR CM1000 (DOCSIS 3.1) and also a NETGEAR R6700v2 router. We never had this issue at our previous residence with the same equipment. However, when we first moved to our apartment, we had similar issues but not at the same frequency. These corrected after about a month or so, but just started again at a much higher frequency a couple days ago. I'm fairly new to troubleshooting the network, so any and all assistance would be greatly appreciated.

 

2018-12-06, 11:49:15 Critical (3) Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=cc:40:d0:26:1d:68;CMTS-MAC=00:01:5c:92:7e:65;CM-QOS=1.1;CM-VER=3.1;
2018-12-06, 11:49:15 Warning (5) Dynamic Range Window violation
2018-12-06, 11:49:15 Warning (5) RNG-RSP CCAP Commanded Power Exceeds Value Corresponding to the Top of the DRW;CM-MAC=cc:40:d0:26:1d:68;CMTS-MAC=00:01:5c:92:7e:65;CM-QOS=1.1;CM-VER=3.1;
2018-12-06, 11:49:15 Warning (5) Dynamic Range Window violation
2018-12-06, 11:49:15 Warning (5) RNG-RSP CCAP Commanded Power Exceeds Value Corresponding to the Top of the DRW;CM-MAC=cc:40:d0:26:1d:68;CMTS-MAC=00:01:5c:92:7e:65;CM-QOS=1.1;CM-VER=3.1;
2018-12-06, 11:49:14 Critical (3) Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=cc:40:d0:26:1d:68;CMTS-MAC=00:01:5c:92:7e:65;CM-QOS=1.1;CM-VER=3.1;
2018-12-06, 11:49:14 Warning (5) Dynamic Range Window violation
2018-12-06, 11:49:14 Warning (5) RNG-RSP CCAP Commanded Power in Excess of 6 dB Below the Value Corresponding to the Top of the DRW;CM-MAC=cc:40:d0:26:1d:68;CMTS-MAC=00:01:5c:92:7e:65;CM-QOS=1.1;CM-VER=3.1;
2018-12-06, 11:49:14 Warning (5) Dynamic Range Window violation
2018-12-06, 11:49:14 Warning (5) RNG-RSP CCAP Commanded Power in Excess of 6 dB Below the Value Corresponding to the Top of the DRW;CM-MAC=cc:40:d0:26:1d:68;CMTS-MAC=00:01:5c:92:7e:65;CM-QOS=1.1;CM-VER=3.1;
2018-12-06, 11:49:05 Critical (3) Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=cc:40:d0:26:1d:68;CMTS-MAC=00:01:5c:92:7e:65;CM-QOS=1.1;CM-VER=3.1;
2018-12-06, 11:41:42 Notice (6) CM-STATUS message sent. Event Type Code: 24; Chan ID: 25 ; DSID: N/A; MAC Addr: N/A; OFDM/OFDMA Profile ID: 1 .;CM-MAC=cc:40:d0:26:1d:68;CMTS-MAC=00:01:5c:92:7e:65;CM-QOS=1.1;CM-VER=3.1;
2018-12-06, 11:41:03 Notice (6) DS profile assignment change. DS Chan ID: 32; Previous Profile: ; New Profile: 1 .;CM-MAC=cc:40:d0:26:1d:68;CMTS-MAC=00:01:5c:92:7e:65;CM-QOS=1.1;CM-VER=3.1;
2018-12-06, 11:40:52 Notice (6) Honoring MDD; IP provisioning mode = IPv6
2018-12-06, 11:40:38 Critical (3) No Ranging Response received - T3 time-out;CM-MAC=cc:40:d0:26:1d:68;CMTS-MAC=00:01:5c:92:7e:65;CM-QOS=1.1;CM-VER=3.1;
2018-12-06, 11:40:27 Critical (3) Received Response to Broadcast Maintenance Request, But no Unicast Maintenance opportunities received - T4 time out;CM-MAC=cc:40:d0:26:1d:68;CMTS-MAC=00:01:5c:92:7e:65;CM-QOS=1.1;CM-VER=3.1;
2018-12-06, 11:40:13 Critical (3) No Ranging Response received - T3 time-out;CM-MAC=cc:40:d0:26:1d:68;CMTS-MAC=00:01:5c:92:7e:65;CM-QOS=1.1;CM-VER=3.1;
2018-12-06, 11:40:12 Critical (3) Received Response to Broadcast Maintenance Request, But no Unicast Maintenance opportunities received - T4 time out;CM-MAC=cc:40:d0:26:1d:68;CMTS-MAC=00:01:5c:92:7e:65;CM-QOS=1.1;CM-VER=3.1;
2018-12-06, 11:36:47 Critical (3) No Ranging Response received - T3 time-out;CM-MAC=cc:40:d0:26:1d:68;CMTS-MAC=00:01:5c:92:7e:65;CM-QOS=1.1;CM-VER=3.1;
2018-12-06, 11:36:37 Notice (6) CM-STATUS message sent. Event Type Code: 7; Chan ID: 63 64 ; DSID: N/A; MAC Addr: N/A; OFDM/OFDMA Profile ID: N/A.;CM-MAC=cc:40:d0:26:1d:68;CMTS-MAC=00:01:5c:92:7e:65;CM-QOS=1.1;CM-VER=3.1;
2018-12-06, 11:36:28 Critical (3) No Ranging Response received - T3 time-out;CM-MAC=cc:40:d0:26:1d:68;CMTS-MAC=00:01:5c:92:7e:65;CM-QOS=1.1;CM-VER=3.1;
2018-12-06, 11:36:20 Critical (3) Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=cc:40:d0:26:1d:68;CMTS-MAC=00:01:5c:92:7e:65;CM-QOS=1.1;CM-VER=3.1;
2018-12-06, 11:36:20 Critical (3) No Ranging Response received - T3 time-out;CM-MAC=cc:40:d0:26:1d:68;CMTS-MAC=00:01:5c:92:7e:65;CM-QOS=1.1;CM-VER=3.1;
2018-12-06, 11:36:19 Critical (3) Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=cc:40:d0:26:1d:68;CMTS-MAC=00:01:5c:92:7e:65;CM-QOS=1.1;CM-VER=3.1;
2018-12-06, 11:36:18 Critical (3) No Ranging Response received - T3 time-out;CM-MAC=cc:40:d0:26:1d:68;CMTS-MAC=00:01:5c:92:7e:65;CM-QOS=1.1;CM-VER=3.1;
2018-12-06, 11:36:18 Critical (3) Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=cc:40:d0:26:1d:68;CMTS-MAC=00:01:5c:92:7e:65;CM-QOS=1.1;CM-VER=3.1;
2018-12-06, 11:36:17 Critical (3) No Ranging Response received - T3 time-out;CM-MAC=cc:40:d0:26:1d:68;CMTS-MAC=00:01:5c:92:7e:65;CM-QOS=1.1;CM-VER=3.1;
2018-12-06, 11:36:17 Critical (3) Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=cc:40:d0:26:1d:68;CMTS-MAC=00:01:5c:92:7e:65;CM-QOS=1.1;CM-VER=3.1;
2018-12-06, 11:36:15 Critical (3) No Ranging Response received - T3 time-out;CM-MAC=cc:40:d0:26:1d:68;CMTS-MAC=00:01:5c:92:7e:65;CM-QOS=1.1;CM-VER=3.1;
2018-12-06, 11:36:15 Critical (3) Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=cc:40:d0:26:1d:68;CMTS-MAC=00:01:5c:92:7e:65;CM-QOS=1.1;CM-VER=3.1;
2018-12-06, 11:36:15 Critical (3) No Ranging Response received - T3 time-out;CM-MAC=cc:40:d0:26:1d:68;CMTS-MAC=00:01:5c:92:7e:65;CM-QOS=1.1;CM-VER=3.1;
2018-12-06, 11:36:15 Critical (3) 16 consecutive T3 timeouts while trying to range on upstream channel 2;CM-MAC=cc:40:d0:26:1d:68;CMTS-MAC=00:01:5c:92:7e:65;CM-QOS=1.1;CM-VER=3.1;
2018-12-06, 11:36:15 Critical (3) Unicast Maintenance Ranging attempted - No response - Retries exhausted;CM-MAC=cc:40:d0:26:1d:68;CMTS-MAC=00:01:5c:92:7e:65;CM-QOS=1.1;CM-VER=3.1;
2018-12-06, 11:36:15 Critical (3) Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=cc:40:d0:26:1d:68;CMTS-MAC=00:01:5c:92:7e:65;CM-QOS=1.1;CM-VER=3.1;
2018-12-06, 11:36:14 Critical (3) 16 consecutive T3 timeouts while trying to range on upstream channel 3;CM-MAC=cc:40:d0:26:1d:68;CMTS-MAC=00:01:5c:92:7e:65;CM-QOS=1.1;CM-VER=3.1;
2018-12-06, 11:36:14 Critical (3) Unicast Maintenance Ranging attempted - No response - Retries exhausted;CM-MAC=cc:40:d0:26:1d:68;CMTS-MAC=00:01:5c:92:7e:65;CM-QOS=1.1;CM-VER=3.1;
2018-12-06, 11:35:07 Critical (3) Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=cc:40:d0:26:1d:68;CMTS-MAC=00:01:5c:92:7e:65;CM-QOS=1.1;CM-VER=3.1;
2018-12-06, 11:30:36 Notice (6) CM-STATUS message sent. Event Type Code: 8; Chan ID: 62 ; DSID: N/A; MAC Addr: N/A; OFDM/OFDMA Profile ID: N/A.;CM-MAC=cc:40:d0:26:1d:68;CMTS-MAC=00:01:5c:92:7e:65;CM-QOS=1.1;CM-VER=3.1;
2018-12-06, 11:29:45 Critical (3) Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=cc:40:d0:26:1d:68;CMTS-MAC=00:01:5c:92:7e:65;CM-QOS=1.1;CM-VER=3.1;
2018-12-06, 11:29:45 Warning (5) Dynamic Range Window violation

 

Frequency start Value
This field below allows you to modify the frequency the cable modem start with its scan during initialization and registration. Enter the new start frequency and restart the cable modem for it to take effect.
Starting Frequency

<tabindex=-1>Startup Procedure
Procedure Status Comment
Acquire Downstream Channel 615000000 Hz Locked
Connectivity State OK Operational
Boot State OK Operational
Security Enable BPI+
IP Provisioning Mode Honor MDD IPv6 only

<tabindex=-1>Downstream Bonded Channels
Channel Lock Status Modulation Channel ID Frequency Power SNR / MER Unerrored Codewords Correctable Codewords Uncorrectable Codewords
1 Locked QAM256 20 615000000 Hz 7.2 dBmV 43.1 dB 89216897 33 116
2 Locked QAM256 1 489000000 Hz 7.5 dBmV 43.1 dB 69423960 17 56
3 Locked QAM256 2 495000000 Hz 7.5 dBmV 43.2 dB 69431950 24 51
4 Locked QAM256 3 507000000 Hz 7.6 dBmV 43.1 dB 69440036 18 56
5 Locked QAM256 4 513000000 Hz 7.4 dBmV 43.2 dB 69446944 12 61
6 Locked QAM256 5 519000000 Hz 7.4 dBmV 43.3 dB 69454309 13 64
7 Locked QAM256 6 525000000 Hz 7.5 dBmV 42.9 dB 69461689 19 59
8 Locked QAM256 7 531000000 Hz 7.4 dBmV 42.8 dB 69469032 16 56
9 Locked QAM256 8 537000000 Hz 7.5 dBmV 42.9 dB 69476508 14 59
10 Locked QAM256 9 543000000 Hz 7.5 dBmV 42.9 dB 69483992 10 64
11 Locked QAM256 10 555000000 Hz 7.5 dBmV 42.9 dB 69491490 13 61
12 Locked QAM256 11 561000000 Hz 7.3 dBmV 43.0 dB 69499094 17 55
13 Locked QAM256 12 567000000 Hz 7.4 dBmV 42.8 dB 69506787 18 55
14 Locked QAM256 13 573000000 Hz 7.3 dBmV 42.7 dB 69513481 12 60
15 Locked QAM256 14 579000000 Hz 7.2 dBmV 42.8 dB 69521848 19 55
16 Locked QAM256 15 585000000 Hz 7.2 dBmV 42.7 dB 69529194 12 63
17 Locked QAM256 16 591000000 Hz 7.3 dBmV 42.8 dB 69536594 14 61
18 Locked QAM256 17 597000000 Hz 7.4 dBmV 42.7 dB 69544191 13 59
19 Locked QAM256 18 603000000 Hz 7.3 dBmV 42.8 dB 69551333 15 68
20 Locked QAM256 19 609000000 Hz 7.3 dBmV 43.0 dB 69558961 17 58
21 Locked QAM256 21 621000000 Hz 7.3 dBmV 43.2 dB 69566586 15 65
22 Locked QAM256 22 627000000 Hz 7.5 dBmV 43.3 dB 69556082 11 62
23 Locked QAM256 23 633000000 Hz 7.5 dBmV 43.4 dB 69557264 19 58
24 Locked QAM256 24 639000000 Hz 7.7 dBmV 43.2 dB 69559017 8 64
25 Locked QAM256 26 645000000 Hz 7.5 dBmV 43.4 dB 69523998 15 57
26 Locked QAM256 27 651000000 Hz 8.0 dBmV 43.6 dB 69531378 11 70
27 Locked QAM256 28 657000000 Hz 7.6 dBmV 43.2 dB 69538874 15 60
28 Locked QAM256 29 663000000 Hz 7.7 dBmV 43.3 dB 69546431 10 70
29 Locked QAM256 30 669000000 Hz 7.9 dBmV 43.2 dB 69553735 16 67
30 Locked QAM256 31 675000000 Hz 7.5 dBmV 42.8 dB 69558206 18 62
31 Locked QAM256 32 681000000 Hz 7.7 dBmV 43.4 dB 69562931 15 64
32 Not Locked Unknown 0 0 Hz 0.0 dBmV 0.0 dB 0 0 0

<tabindex=-1>Upstream Bonded Channels
Channel Lock Status Modulation Channel ID Frequency Power
1 Locked ATDMA 61 36500000 Hz 41.0 dBmV
2 Locked ATDMA 62 30100000 Hz 42.3 dBmV
3 Locked ATDMA 63 23700000 Hz 42.8 dBmV
4 Locked ATDMA 64 17300000 Hz 43.5 dBmV
5 Not Locked Unknown 0 0 Hz 0.0 dBmV
6 Not Locked Unknown 0 0 Hz 0.0 dBmV
7 Not Locked Unknown 0 0 Hz 0.0 dBmV
8 Not Locked Unknown 0 0 Hz 0.0 dBmV

<tabindex=-1>Downstream OFDM Channels
Channel Lock Status Modulation / Profile ID Channel ID Frequency Power SNR / MER Active Subcarrier Number Range Unerrored Codewords Correctable Codewords Uncorrectable Codewords
1 Locked 0, 1, 255 25 693000000 Hz 8.2 dBmV 41.8 dB 1108 ~ 2987 125993390 122252675 0
2 Not Locked 0, 255 0 0 Hz 3.9 dBmV 0.0 dB 0 ~ 4095 0 0 0

<tabindex=-1>Upstream OFDMA Channels
Channel Lock Status Modulation / Profile ID Channel ID Frequency Power
1 Not Locked Unknown 0 0 Hz 0 dBmV
2 Not Locked Unknown 0 0 Hz 0 dBmV
Expert

Re: Intermittent Network Shutdown

Even though the signal stats look o/k at that snapshot in time, the error log entries confirm that something is going on.

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.

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



I am not a Comcast Employee.
I am a Customer Expert volunteering my time to help other customers here in the Forums.
We ask that you post publicly so people with similar questions may benefit from the conversation.
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New Poster

Re: Intermittent Network Shutdown

Thank you very much!

Official Employee

Re: Intermittent Network Shutdown

Hello mhogan4491. Welcome to the Xfinity Forums and thank you for creating your first post. I can assist with troubleshooting your intermittent connectivity issues. I'd like to start with polling the CMTS for real-time and historical RF signal reports from your modem. I can also check your local Node/Plant for any degradation or error reports. Please send me a private message and include your full name so I can access your equipment. 

 

To send me a private, message click my name (ComcastJoeTru) to view my profile. Then click "Send a message" and private message me. 
 


I am an Official Comcast Employee.
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!