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Intermittent Connectivity Issues

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Intermittent Connectivity Issues

Hello all,

 

Like some others I see on this forum, I'm having a problem where my connection will occasionally die for a few seconds to a few minutes. It seems to happen more during busy times (evenings), but has happened other times as well.

 

We have called support, tried everything they suggested, still have the same problems. We also had a tech come out, he couldn't find any problems with the downstream connection. He tried moving our cable to a different place in the box attached to the apartment complex, but we're still having problems.

 

We are using a NETGEAR CM400 modem. The upstream light on the modem will sometimes flash when we're having problems, but other times it won't (or maybe I just haven't noticed it). The router is a Buffalo WZR-600DHP, but we tried having a computer plugged directly into the modem for about 10 hours and the problem still showed up a few times, so we don't think it's the router.

 

Here is the downstream/upstream information:

Downstream Bonded Channels
Channel Lock Status Modulation Channel ID Frequency Power SNR Correctables UnCorrectables
1 Locked QAM 256 1 507000000 Hz 2.3 dBmV 37.9 dB 1877 5779
2 Locked QAM 256 2 513000000 Hz 2.2 dBmV 38.2 dB 1101 2438
3 Locked QAM 256 3 519000000 Hz 1.9 dBmV 37.9 dB 1310 5123
4 Locked QAM 256 4 525000000 Hz 2.0 dBmV 38.2 dB 1618 4841
5 Locked QAM 256 5 531000000 Hz 1.7 dBmV 38.6 dB 1089 3502
6 Locked QAM 256 6 537000000 Hz 1.7 dBmV 38.2 dB 1190 4245
7 Locked QAM 256 7 543000000 Hz 1.8 dBmV 38.6 dB 2526 9687
8 Locked QAM 256 8 549000000 Hz 2.0 dBmV 38.6 dB 1967 10497

Upstream Bonded Channels
Channel Lock Status US Channel Type Channel ID Symbol Rate Frequency Power
1 Locked ATDMA 88 5120 Ksym/sec 17300000 Hz 40.8 dBmV
2 Locked ATDMA 87 5120 Ksym/sec 23700000 Hz 41.5 dBmV
3 Locked ATDMA 86 5120 Ksym/sec 30100000 Hz 42.8 dBmV
4 Locked ATDMA 85 5120 Ksym/sec 36500000 Hz 42.0 dBmV

 

 

Here are the modem error logs (the "Lost MDD Timeout" messages are new, but the ranging request retries and T3/T4 timeout messages have accompanied this problem in the past):

Time Priority Description
May 26 15:14:41 2018 Warning (5) Lost MDD Timeout
May 26 15:14:41 2018 Warning (5) Lost MDD Timeout
May 26 15:14:41 2018 Warning (5) Lost MDD Timeout
May 26 15:14:41 2018 Warning (5) Lost MDD Timeout
May 26 15:14:41 2018 Warning (5) Lost MDD Timeout
May 26 15:14:41 2018 Warning (5) Lost MDD Timeout
May 26 15:14:41 2018 Warning (5) Lost MDD Timeout
May 26 15:14:41 2018 Warning (5) Lost MDD Timeout
May 26 15:14:41 2018 Warning (5) Lost MDD Timeout
May 26 15:14:41 2018 Warning (5) Lost MDD Timeout
May 26 15:14:41 2018 Warning (5) Lost MDD Timeout
May 26 15:14:41 2018 Warning (5) Lost MDD Timeout
May 26 15:14:41 2018 Warning (5) Lost MDD Timeout
May 26 15:14:41 2018 Warning (5) Lost MDD Timeout
May 26 15:14:41 2018 Warning (5) Lost MDD Timeout
May 26 15:14:41 2018 Warning (5) Lost MDD Timeout
May 26 15:14:41 2018 Warning (5) Lost MDD Timeout
May 26 15:14:41 2018 Warning (5) Lost MDD Timeout
May 26 15:14:41 2018 Warning (5) Lost MDD Timeout
May 26 15:14:41 2018 Warning (5) Lost MDD Timeout
May 26 15:14:41 2018 Warning (5) Lost MDD Timeout
May 26 15:14:41 2018 Warning (5) Lost MDD Timeout
May 26 15:14:41 2018 Warning (5) Lost MDD Timeout
May 26 15:14:41 2018 Warning (5) Lost MDD Timeout
May 26 15:14:41 2018 Warning (5) Lost MDD Timeout
May 26 15:14:41 2018 Warning (5) Lost MDD Timeout
May 26 15:14:41 2018 Warning (5) Lost MDD Timeout
May 26 15:14:41 2018 Warning (5) Lost MDD Timeout
May 26 15:14:41 2018 Warning (5) Lost MDD Timeout
May 26 15:14:41 2018 Warning (5) Lost MDD Timeout
May 26 15:14:41 2018 Warning (5) Lost MDD Timeout
May 26 15:20:56 2018 Critical (3) Received Response to Broadcast Maintenance Request, But no Unicast Maintenance opportunities received - T4 time out
May 26 15:21:20 2018 Warning (5) MIMO Event MIMO: Stored MIMO=-1 post cfg file MIMO=-1
May 26 19:19:20 2018 Critical (3) No Ranging Response received - T3 time-out
May 26 19:24:10 2018 Critical (3) Ranging Request Retries exhausted
May 26 19:24:10 2018 Critical (3) Unicast Maintenance Ranging attempted - No response - Retries exhausted
May 26 19:24:11 2018 Critical (3) No Ranging Response received - T3 time-out
May 26 19:24:47 2018 Critical (3) Ranging Request Retries exhausted
May 26 19:24:47 2018 Critical (3) Unicast Maintenance Ranging attempted - No response - Retries exhausted
May 26 19:24:48 2018 Critical (3) No Ranging Response received - T3 time-out
May 28 15:01:33 2018 Warning (5) MIMO Event MIMO: Stored MIMO=-1 post cfg file MIMO=-1
May 28 15:01:37 2018 Critical (3) No Ranging Response received - T3 time-out
May 30 11:40:47 2018 Critical (3) Received Response to Broadcast Maintenance Request, But no Unicast Maintenance opportunities received - T4 time out
May 30 11:41:13 2018 Warning (5) MIMO Event MIMO: Stored MIMO=-1 post cfg file MIMO=-1
May 30 12:17:20 2018 Critical (3) No Ranging Response received - T3 time-out
May 30 12:20:30 2018 Critical (3) Ranging Request Retries exhausted
May 30 12:20:30 2018 Critical (3) Unicast Maintenance Ranging attempted - No response - Retries exhausted
May 30 12:20:42 2018 Critical (3) Ranging Request Retries exhausted
May 30 12:20:42 2018 Critical (3) Unicast Maintenance Ranging attempted - No response - Retries exhausted
May 30 12:20:42 2018 Critical (3) No Ranging Response received - T3 time-out
May 30 12:20:50 2018 Critical (3) Ranging Request Retries exhausted
May 30 12:20:50 2018 Critical (3) Unicast Maintenance Ranging attempted - No response - Retries exhausted
May 30 12:20:51 2018 Critical (3) No Ranging Response received - T3 time-out
May 30 12:24:42 2018 Critical (3) Received Response to Broadcast Maintenance Request, But no Unicast Maintenance opportunities received - T4 time out
May 30 12:25:15 2018 Critical (3) No Ranging Response received - T3 time-out
May 30 12:25:43 2018 Warning (5) MIMO Event MIMO: Stored MIMO=-1 post cfg file MIMO=-1
May 30 12:42:36 2018 Critical (3) No Ranging Response received - T3 time-out
May 30 12:43:20 2018 Critical (3) Ranging Request Retries exhausted
May 30 12:43:20 2018 Critical (3) Unicast Maintenance Ranging attempted - No response - Retries exhausted
May 30 12:43:20 2018 Critical (3) No Ranging Response received - T3 time-out
May 30 13:08:56 2018 Critical (3) Ranging Request Retries exhausted
May 30 13:08:56 2018 Critical (3) Unicast Maintenance Ranging attempted - No response - Retries exhausted
May 30 13:09:02 2018 Critical (3) Ranging Request Retries exhausted
May 30 13:09:02 2018 Critical (3) Unicast Maintenance Ranging attempted - No response - Retries exhausted
May 30 13:09:05 2018 Critical (3) Ranging Request Retries exhausted
May 30 13:09:05 2018 Critical (3) Unicast Maintenance Ranging attempted - No response - Retries exhausted
May 30 13:09:20 2018 Critical (3) No Ranging Response received - T3 time-out
May 30 17:59:53 2018 Critical (3) Ranging Request Retries exhausted
May 30 17:59:54 2018 Critical (3) Unicast Maintenance Ranging attempted - No response - Retries exhausted
May 30 18:00:17 2018 Critical (3) No Ranging Response received - T3 time-out
 
 
Please let me know if there's any other info I should get that might help diagnose the problem. Thanks!
Expert
Expert

Re: Intermittent Connectivity Issues

Hi @cojoco

Your power levels look good, but your error log confirms your issues. 

 

I've asked an employee to check the CMTS for real-time and historical RF signal reports from your modem. They can also check your local node/plant for any degradation or error reports. You can expect a reply in this thread. 

Official Employee

Re: Intermittent Connectivity Issues

Hello, 

I would like to look into this for you from here. To protect the privacy of your account, please send me a private message verifying your full name, street address including city, state, and zip code (and apartment number if one is associated), and the full account number or phone number associated with your services. To send a private message click on my name, then click private message me.