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random internet disconnects - netgear c7000v2

Regular Visitor

random internet disconnects - netgear c7000v2

Hoping someone from xfinity will be able to help.  I called cs today and they pushed me to netgear.  Called netgear and they pushed me back to isp.  I have a customer owned netgear c7000v2 with firmware V1.03.01 (which I think is newer than needed).  Starting 3 days ago, about 5-10 times a day my internet connection drops for a minute or two and then comes back.  Logs / speeds are posted below.  The modem is only 5 months old and has been flawless up until now.  It will also work for hours at a time before dropping.  Netgear feels it could be noise on the line at a certain time that is causing the random drops .  Any help or suggestions would be appreciated.   I have checked all inside and outside connections to the box, opened box (all clean), validated ground is tight and properly grounded to house electrical system.  I have no splitters as this is internet only and runs about 15 foot from box to modem.  New overhead and "indoor" cables were run when the service was installed in April of this year. 

 

Thanks

2019-9-19, 19:48:00 Critical (3) Received Response to Broadcast Maintenance Request, But no Unicast Maintenance opportunities received - T4 time out;CM-MAC=10:0c:6b:6b:e5:a8;CMTS-MAC=00:01:5c:97:42:46;CM-QOS=1.1;CM-VER=3.0;
2019-9-19, 14:41:30 Critical (3) Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=10:0c:6b:6b:e5:a8;CMTS-MAC=00:01:5c:97:42:46;CM-QOS=1.1;CM-VER=3.0;
2019-9-19, 14:30:25 Critical (3) Received Response to Broadcast Maintenance Request, But no Unicast Maintenance opportunities received - T4 time out;CM-MAC=10:0c:6b:6b:e5:a8;CMTS-MAC=00:01:5c:97:42:46;CM-QOS=1.1;CM-VER=3.0;
2019-9-19, 14:01:17 Critical (3) Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=10:0c:6b:6b:e5:a8;CMTS-MAC=00:01:5c:97:42:46;CM-QOS=1.1;CM-VER=3.0;
2019-9-19, 13:57:09 Critical (3) Received Response to Broadcast Maintenance Request, But no Unicast Maintenance opportunities received - T4 time out;CM-MAC=10:0c:6b:6b:e5:a8;CMTS-MAC=00:01:5c:97:42:46;CM-QOS=1.1;CM-VER=3.0;
2019-9-19, 13:52:31 Critical (3) Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=10:0c:6b:6b:e5:a8;CMTS-MAC=00:01:5c:97:42:46;CM-QOS=1.1;CM-VER=3.0;
2019-9-19, 13:37:51 Critical (3) No Ranging Response received - T3 time-out;CM-MAC=10:0c:6b:6b:e5:a8;CMTS-MAC=00:01:5c:97:42:46;CM-QOS=1.0;CM-VER=3.0;
2019-9-19, 13:37:35 Critical (3) Received Response to Broadcast Maintenance Request, But no Unicast Maintenance opportunities received - T4 time out;CM-MAC=10:0c:6b:6b:e5:a8;CMTS-MAC=00:01:5c:97:42:46;CM-QOS=1.1;CM-VER=3.0;
2019-9-19, 10:21:56 Critical (3) Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=10:0c:6b:6b:e5:a8;CMTS-MAC=00:01:5c:97:42:46;CM-QOS=1.1;CM-VER=3.0;
2019-9-19, 10:17:53 Critical (3) Received Response to Broadcast Maintenance Request, But no Unicast Maintenance opportunities received - T4 time out;CM-MAC=10:0c:6b:6b:e5:a8;CMTS-MAC=00:01:5c:97:42:46;CM-QOS=1.1;CM-VER=3.0;
2019-9-19, 10:13:15 Critical (3) Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=10:0c:6b:6b:e5:a8;CMTS-MAC=00:01:5c:97:42:46;CM-QOS=1.1;CM-VER=3.0;
2019-9-19, 09:26:55 Critical (3) Received Response to Broadcast Maintenance Request, But no Unicast Maintenance opportunities received - T4 time out;CM-MAC=10:0c:6b:6b:e5:a8;CMTS-MAC=00:01:5c:97:42:46;CM-QOS=1.1;CM-VER=3.0;
2019-9-19, 09:22:17 Critical (3) Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=10:0c:6b:6b:e5:a8;CMTS-MAC=00:01:5c:97:42:46;CM-QOS=1.1;CM-VER=3.0;
2019-9-19, 09:14:46 Critical (3) Received Response to Broadcast Maintenance Request, But no Unicast Maintenance opportunities received - T4 time out;CM-MAC=10:0c:6b:6b:e5:a8;CMTS-MAC=00:01:5c:97:42:46;CM-QOS=1.1;CM-VER=3.0;
2019-9-19, 08:09:24 Critical (3) Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=10:0c:6b:6b:e5:a8;CMTS-MAC=00:01:5c:97:42:46;CM-QOS=1.1;CM-VER=3.0;
2019-9-19, 05:55:44 Critical (3) Received Response to Broadcast Maintenance Request, But no Unicast Maintenance opportunities received - T4 time out;CM-MAC=10:0c:6b:6b:e5:a8;CMTS-MAC=00:01:5c:97:42:46;CM-QOS=1.1;CM-VER=3.0;
2019-9-19, 05:51:06 Critical (3) Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=10:0c:6b:6b:e5:a8;CMTS-MAC=00:01:5c:97:42:46;CM-QOS=1.1;CM-VER=3.0;
2019-9-19, 05:36:34 Critical (3) Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=10:0c:6b:6b:e5:a8;CMTS-MAC=00:01:5c:97:42:46;CM-QOS=1.0;CM-VER=3.0;
2019-9-19, 05:36:10 Critical (3) Received Response to Broadcast Maintenance Request, But no Unicast Maintenance opportunities received - T4 time out;CM-MAC=10:0c:6b:6b:e5:a8;CMTS-MAC=00:01:5c:97:42:46;CM-QOS=1.1;CM-VER=3.0;
2019-9-19, 05:31:31 Critical (3) Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=10:0c:6b:6b:e5:a8;CMTS-MAC=00:01:5c:97:42:46;CM-QOS=1.1;CM-VER=3.0;
2019-9-19, 04:14:27 Critical (3) No Ranging Response received - T3 time-out;CM-MAC=10:0c:6b:6b:e5:a8;CMTS-MAC=00:01:5c:97:42:46;CM-QOS=1.0;CM-VER=3.0;
2019-9-19, 04:14:12 Critical (3) Received Response to Broadcast Maintenance Request, But no Unicast Maintenance opportunities received - T4 time out;CM-MAC=10:0c:6b:6b:e5:a8;CMTS-MAC=00:01:5c:97:42:46;CM-QOS=1.1;CM-VER=3.0;
2019-9-19, 04:04:10 Critical (3) Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=10:0c:6b:6b:e5:a8;CMTS-MAC=00:01:5c:97:42:46;CM-QOS=1.1;CM-VER=3.0;
1970-1-1, 00:00:44 Critical (3) No Ranging Response received - T3 time-out;CM-MAC=10:0c:6b:6b:e5:a8;CMTS-MAC=00:01:5c:97:42:46;CM-QOS=1.0;CM-VER=3.0;
1970-1-1, 00:00:37 Critical (3) SYNC Timing Synchronization failure - Failed to acquire FEC framing;CM-MAC=10:0c:6b:6b:e5:a8;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.0;CM-VER=3.0;
2019-9-19, 01:10:27 Critical (3) No Ranging Response received - T3 time-out;CM-MAC=10:0c:6b:6b:e5:a8;CMTS-MAC=00:01:5c:97:42:46;CM-QOS=1.0;CM-VER=3.0;
2019-9-19, 01:10:04 Critical (3) Received Response to Broadcast Maintenance Request, But no Unicast Maintenance opportunities received - T4 time out;CM-MAC=10:0c:6b:6b:e5:a8;CMTS-MAC=00:01:5c:97:42:46;CM-QOS=1.1;CM-VER=3.0;
2019-9-19, 01:05:26 Critical (3) Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=10:0c:6b:6b:e5:a8;CMTS-MAC=00:01:5c:97:42:46;CM-QOS=1.1;CM-VER=3.0;
2019-9-19, 00:51:10 Critical (3) No Ranging Response received - T3 time-out;CM-MAC=10:0c:6b:6b:e5:a8;CMTS-MAC=00:01:5c:97:42:46;CM-QOS=1.0;CM-VER=3.0;
2019-9-19, 00:50:43 Critical (3) Received Response to Broadcast Maintenance Request, But no Unicast Maintenance opportunities received - T4 time out;CM-MAC=10:0c:6b:6b:e5:a8;CMTS-MAC=00:01:5c:97:42:46;CM-QOS=1.1;CM-VER=3.0;
2019-9-19, 00:44:24 Critical (3) Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=10:0c:6b:6b:e5:a8;CMTS-MAC=00:01:5c:97:42:46;CM-QOS=1.1;CM-VER=3.0;
2019-9-18, 23:20:49 Critical (3) Received Response to Broadcast Maintenance Request, But no Unicast Maintenance opportunities received - T4 time out;CM-MAC=10:0c:6b:6b:e5:a8;CMTS-MAC=00:01:5c:97:42:46;CM-QOS=1.1;CM-VER=3.0;
2019-9-18, 23:15:46 Critical (3) Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=10:0c:6b:6b:e5:a8;CMTS-MAC=00:01:5c:97:42:46;CM-QOS=1.1;CM-VER=3.0;
2019-9-18, 22:45:40 Critical (3) Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=10:0c:6b:6b:e5:a8;CMTS-MAC=00:01:5c:97:42:46;CM-QOS=1.0;CM-VER=3.0;
2019-9-18, 22:45:26 Critical (3) Received Response to Broadcast Maintenance Request, But no Unicast Maintenance opportunities received - T4 time out;CM-MAC=10:0c:6b:6b:e5:a8;CMTS-MAC=00:01:5c:97:42:46;CM-QOS=1.1;CM-VER=3.0;
2019-9-18, 13:14:59 Critical (3)

Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=10:0c:6b:6b:e5:a8;CMTS-MAC=00:01:5c:97:42:46;CM-QOS=1.1;CM-VER=3.0;

 

 

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
 
Startup Procedure
Procedure Status Comment
Acquire Downstream Channel 471000000 Hz Locked
Connectivity State OK Operational
Boot State OK Operational
Security Enabled BPI+
IP Provisioning Mode Honor MDD honorMdd(4)
 
Downstream Bonded Channels
Channel Lock Status Modulation Channel ID Frequency Power SNR Correctables Uncorrectables
1 Locked QAM256 16 471000000 Hz 4.4 dBmV 40.2 dB 28 101
2 Locked QAM256 1 381000000 Hz 5.8 dBmV 41 dB 25 106
3 Locked QAM256 2 387000000 Hz 5.5 dBmV 40.8 dB 20 128
4 Locked QAM256 3 393000000 Hz 5.1 dBmV 40.4 dB 43 87
5 Locked QAM256 4 399000000 Hz 5 dBmV 39.6 dB 25 108
6 Locked QAM256 5 405000000 Hz 4.7 dBmV 40.3 dB 26 141
7 Locked QAM256 6 411000000 Hz 3.8 dBmV 40 dB 30 143
8 Locked QAM256 7 417000000 Hz 2.9 dBmV 39.6 dB 47 89
9 Locked QAM256 8 423000000 Hz 3.7 dBmV 39.8 dB 40 121
10 Locked QAM256 9 429000000 Hz 4.3 dBmV 40.1 dB 36 117
11 Locked QAM256 10 435000000 Hz 4.6 dBmV 40.2 dB 29 116
12 Locked QAM256 11 441000000 Hz 4.4 dBmV 40.1 dB 42 101
13 Locked QAM256 12 447000000 Hz 4.3 dBmV 40.1 dB 42 87
14 Locked QAM256 13 453000000 Hz 4.5 dBmV 40.2 dB 48 81
15 Locked QAM256 14 459000000 Hz 4.5 dBmV 40.2 dB 45 85
16 Locked QAM256 15 465000000 Hz 4.4 dBmV 40.2 dB 32 96
17 Locked QAM256 17 477000000 Hz 4.3 dBmV 39.4 dB 0 0
18 Locked QAM256 18 483000000 Hz 4.2 dBmV 39.3 dB 0 0
19 Locked QAM256 19 489000000 Hz 4.2 dBmV 39.4 dB 0 0
20 Locked QAM256 20 495000000 Hz 3.9 dBmV 39 dB 0 0
21 Not Locked Unknown 0 0 Hz 0.0 dBmV 0.0 dB 0 0
22 Not Locked Unknown 0 0 Hz 0.0 dBmV 0.0 dB 0 0
23 Not Locked Unknown 0 0 Hz 0.0 dBmV 0.0 dB 0 0
24 Not Locked Unknown 0 0 Hz 0.0 dBmV 0.0 dB 0 0
 
Upstream Bonded Channels
Channel Lock Status US Channel Type Channel ID Symbol Rate Frequency Power
1 Locked ATDMA 11 5120 Ksym/sec 25000000 Hz 48 dBmV
2 Locked ATDMA 10 5120 Ksym/sec 18600000 Hz 47.3 dBmV
3 Not Locked Unknown 0 0 Ksym/sec 0 Hz 0.0 dBmV
4 Not Locked Unknown 0 0 Ksym/sec 0 Hz 0.0 dBmV
5 Not Locked Unknown 0 0 Ksym/sec 0 Hz 0.0 dBmV
6 Not Locked Unknown 0 0 Ksym/sec 0 Hz 0.0 dBmV
7 Not Locked Unknown 0 0 Ksym/sec 0 Hz 0.0 dBmV
8 Not Locked Unknown 0 0 Ksym/sec 0 Hz 0.0 dBmV
 
Extended Upstream Transmit Power
Enable Extended Upstream Transmit Power
 
Current System Time:Thu Sep 19 21:12:43 2019
System Up Time:00:20:03
Regular Visitor

Re: random internet disconnects - netgear c7000v2

Here is another snapshot of the connection.  Is the upstream power too high / fluxuate that much?

 

Starting Frequency
 
Startup Procedure
Procedure Status Comment
Acquire Downstream Channel 471000000 Hz Locked
Connectivity State OK Operational
Boot State OK Operational
Security Enabled BPI+
IP Provisioning Mode Honor MDD honorMdd(4)
 
Downstream Bonded Channels
Channel Lock Status Modulation Channel ID Frequency Power SNR Correctables Uncorrectables
1 Locked QAM256 16 471000000 Hz 4.3 dBmV 40.2 dB 7014 1836
2 Locked QAM256 1 381000000 Hz 5.3 dBmV 40.9 dB 8869 2855
3 Locked QAM256 2 387000000 Hz 5.1 dBmV 40.7 dB 8990 2412
4 Locked QAM256 3 393000000 Hz 4.6 dBmV 40.3 dB 8912 2231
5 Locked QAM256 4 399000000 Hz 4.5 dBmV 39.5 dB 8670 2419
6 Locked QAM256 5 405000000 Hz 3.8 dBmV 40.1 dB 8907 2260
7 Locked QAM256 6 411000000 Hz 2.7 dBmV 39.7 dB 8901 2321
8 Locked QAM256 7 417000000 Hz 3.5 dBmV 40 dB 8450 2305
9 Locked QAM256 8 423000000 Hz 3.9 dBmV 40.1 dB 8140 2438
10 Locked QAM256 9 429000000 Hz 4.2 dBmV 40.3 dB 7875 1902
11 Locked QAM256 10 435000000 Hz 4.4 dBmV 40.3 dB 7834 1850
12 Locked QAM256 11 441000000 Hz 4.3 dBmV 40.3 dB 7498 1945
13 Locked QAM256 12 447000000 Hz 4.1 dBmV 40.2 dB 7829 1660
14 Locked QAM256 13 453000000 Hz 4.3 dBmV 40.4 dB 7250 1976
15 Locked QAM256 14 459000000 Hz 4.3 dBmV 40.3 dB 7171 1971
16 Locked QAM256 15 465000000 Hz 4.3 dBmV 40.3 dB 7060 1773
17 Locked QAM256 17 477000000 Hz 4.3 dBmV 39.9 dB 0 0
18 Locked QAM256 18 483000000 Hz 4.2 dBmV 39.4 dB 0 0
19 Locked QAM256 19 489000000 Hz 4.2 dBmV 39.9 dB 0 0
20 Locked QAM256 20 495000000 Hz 3.9 dBmV 39.3 dB 0 0
21 Not Locked Unknown 0 0 Hz 0.0 dBmV 0.0 dB 0 0
22 Not Locked Unknown 0 0 Hz 0.0 dBmV 0.0 dB 0 0
23 Not Locked Unknown 0 0 Hz 0.0 dBmV 0.0 dB 0 0
24 Not Locked Unknown 0 0 Hz 0.0 dBmV 0.0 dB 0 0
 
Upstream Bonded Channels
Channel Lock Status US Channel Type Channel ID Symbol Rate Frequency Power
1 Locked ATDMA 11 5120 Ksym/sec 25000000 Hz 54 dBmV
2 Locked ATDMA 10 5120 Ksym/sec 18600000 Hz 54 dBmV
3 Not Locked Unknown 0 0 Ksym/sec 0 Hz 0.0 dBmV
4 Not Locked Unknown 0 0 Ksym/sec 0 Hz 0.0 dBmV
5 Not Locked Unknown 0 0 Ksym/sec 0 Hz 0.0 dBmV
6 Not Locked Unknown 0 0 Ksym/sec 0 Hz 0.0 dBmV
7 Not Locked Unknown 0 0 Ksym/sec 0 Hz 0.0 dBmV
8 Not Locked Unknown 0 0 Ksym/sec 0 Hz 0.0 dBmV
Expert

Re: random internet disconnects - netgear c7000v2

The upstream power too high /out of spec in the second screenshot. That can cause random disconnects, spontaneous re-booting of the modem, speed, packet loss, and latency problems.

In a self troubleshooting effort to try to obtain better connectivity / more wiggle room, check to see if there are there any excess/unneeded coax cable splitters in the line leading to the modem that can be eliminated/re-configured. Any splitters that remain should be high quality and cable rated for 5-1002 MHz, bi-directional, and no gold colored garbage types like GE, RadioShack, RCA, Philips, Leviton, Magnavox, and Rocketfish from big box stores like Home Depot, Lowes, Target, Wal-Mart etc. Splitters should be swapped with known to be good / new ones to test

If there aren't any unneeded splitters that can be eliminated and if your coax wiring setup can't be reconfigured so that there is a single two way splitter connected directly off of the drop from the street/pole with one port feeding the modem and the other port feeding the rest of the house/equipment with additional splits as needed, and you've checked all the wiring and fittings for integrity and tightness and refresh them by taking them apart then check for and clean off any corrosion / oxidation on the center wire and put them back together again, then perhaps it's best to book a tech visit to investigate and correct.



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