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user_b8b6f4
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Wednesday, May 19th, 2021 4:34 PM

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Modem troubles - Dynamic Range Window violation - Unicast Ranging Received Abort Response - Re-initializing - T3 - T4

Good Afternoon,

I have been having sporadic connection issues with my home internet. What will occur is my internet will be working, then will cease, then will restart operation again within a minute or so. 

I have traced the issue to my modem, or at least I have found error logs that coincide with the issue I am seeing. I did this by setting up command prompt windows to ping the IP address of my router from my PC while also pinging the xfinity server that my modem communicates with. During these events, I still have successful pings to the router but not to the server outside my home. 

I am using a Netgear CM500-100NAS modem. I have already checked the coax connection. Unplugged and replugged the coax connections. Powered down for 2 mins while I was doing this etc and I am still having the same issues. At this point I believe this could be a infrastructure issue outside of my home. But I am curious for feedback on anything else I can troubleshoot. 

It seems that I will have a lot of these issues happen in a shorter timeframe (hours)...and then can go hours (12+) without seeing anything. 

I have been receiving the following errors. I also pasted the downstream/upstream info below. There are not many correctables as I tried again recently to power cycle the device and checked the connections again more closely. Before I did this however I did note that all the uncorrectables were only on a single channel (9 if memory serves). I thought that was rather odd but could be useful to know. 

My modem has the latest firmware - V1.01.14 and I only have a single coax going from the home entry point directly to the modem (no switches/splitters involved).

Thanks for your help!

Time Priority Description
2021-5-19, 11:16:54 Notice (6) Honoring MDD; IP provisioning mode = IPv6
2021-5-19, 11:16:39 Critical (3) No Ranging Response received - T3 time-out
2021-5-19, 11:16:30 Critical (3) Received Response to Broadcast Maintenance Request, But no Unicast Maintenance opportunities received - T4 time out
2021-5-19, 11:16:21 Warning (5) Dynamic Range Window violation
2021-5-19, 11:16:17 Critical (3) Unicast Ranging Received Abort Response - Re-initializing 
2021-5-19, 11:16:11 Warning (5) Dynamic Range Window violation
2021-5-19, 11:16:10 Critical (3) Received Response to Broadcast Maintenance Request, But no Unicast Maintenance opportunities received - T4 time out
2021-5-19, 11:16:01 Warning (5) Dynamic Range Window violation
2021-5-19, 11:15:57 Critical (3) Unicast Ranging Received Abort Response - Re-initializing 
2021-5-19, 11:15:41 Warning (5) Dynamic Range Window violation
2021-5-19, 11:15:37 Critical (3) Unicast Ranging Received Abort Response - Re-initializing 
2021-5-19, 11:11:22 Warning (5) Dynamic Range Window violation

Downstream Bonded Channels
Channel Lock Status Modulation Channel ID Frequency Power SNR Correctables Uncorrectables
1 Locked QAM256 41 693000000 Hz 1.1 dBmV 36.8 dB 0 0
2 Locked QAM256 29 621000000 Hz 1.5 dBmV 38 dB 0 0
3 Locked QAM256 30 627000000 Hz 1.8 dBmV 38 dB 0 0
4 Locked QAM256 31 633000000 Hz 1.8 dBmV 37.7 dB 0 0
5 Locked QAM256 32 639000000 Hz 1.2 dBmV 37.2 dB 0 0
6 Locked QAM256 33 645000000 Hz 1.2 dBmV 37.3 dB 0 0
7 Locked QAM256 34 651000000 Hz 1 dBmV 37.2 dB 0 0
8 Locked QAM256 35 657000000 Hz 1.6 dBmV 37.3 dB 0 0
9 Locked QAM256 36 663000000 Hz 1.8 dBmV 37.4 dB 0 0
10 Locked QAM256 37 669000000 Hz 1.5 dBmV 37.2 dB 0 0
11 Locked QAM256 38 675000000 Hz 1.2 dBmV 36.7 dB 0 0
12 Locked QAM256 39 681000000 Hz 1.3 dBmV 37 dB 0 0
13 Locked QAM256 40 687000000 Hz 1.1 dBmV 36.9 dB 0 0
14 Locked QAM256 42 699000000 Hz 0.5 dBmV 36.5 dB 0 0
15 Locked QAM256 43 705000000 Hz 0.7 dBmV 36.6 dB 0 0
16 Locked QAM256 44 711000000 Hz 1.1 dBmV 36.7 dB 1 0
 
Upstream Bonded Channels
Channel Lock Status US Channel Type Channel ID Symbol Rate Frequency Power
1 Locked ATDMA 4 5120 Ksym/sec 16400000 Hz 40.9 dBmV
2 Locked ATDMA 1 5120 Ksym/sec 35600000 Hz 44.7 dBmV
3 Locked ATDMA 2 5120 Ksym/sec 29200000 Hz 44.5 dBmV
4 Locked ATDMA 3 5120 Ksym/sec 22800000 Hz 44.4 dBmV

Question

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4 years ago

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user_b8b6f4

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4 years ago

Running for 2 days now. Still getting the same sorts of errors. Here is updated log info. 

2021-5-21, 07:37:40 Warning (5) Dynamic Range Window violation
2021-5-21, 07:36:50 Critical (3) Received Response to Broadcast Maintenance Request, But no Unicast Maintenance opportunities received - T4 time out
2021-5-21, 07:35:57 Notice (6) Honoring MDD; IP provisioning mode = IPv6
2021-5-21, 07:35:48 Critical (3) No Ranging Response received - T3 time-out
2021-5-21, 07:35:38 Critical (3) Received Response to Broadcast Maintenance Request, But no Unicast Maintenance opportunities received - T4 time out;
2021-5-21, 07:35:30 Warning (5) Dynamic Range Window violation
2021-5-21, 07:35:26 Critical (3) Unicast Ranging Received Abort Response - Re-initializing MAC;
2021-5-21, 07:35:20 Warning (5) Dynamic Range Window violation
2021-5-21, 07:35:18 Critical (3) Received Response to Broadcast Maintenance Request, But no Unicast Maintenance opportunities received - T4 time out
2021-5-21, 07:35:10 Warning (5) Dynamic Range Window violation
2021-5-21, 07:35:06 Critical (3) Unicast Ranging Received Abort Response - Re-initializing MAC
2021-5-21, 07:34:50 Warning (5) Dynamic Range Window violation
2021-5-21, 07:34:46 Critical (3) Unicast Ranging Received Abort Response - Re-initializing MAC
2021-5-21, 07:34:30 Warning (5) Dynamic Range Window violation
2021-5-21, 07:33:39 Critical (3) Received Response to Broadcast Maintenance Request, But no Unicast Maintenance opportunities received - T4 time out
2021-5-21, 07:33:06 Critical (3) Unicast Ranging Received Abort Response - Re-initializing MAC
2021-5-21, 07:32:30 Warning (5) Dynamic Range Window violation
2021-5-21, 07:25:19 Critical (3) Received Response to Broadcast Maintenance Request, But no Unicast Maintenance opportunities received - T4 time out
2021-5-21, 07:25:11 Warning (5) Dynamic Range Window violation
2021-5-21, 07:24:47 Critical (3) Unicast Ranging Received Abort Response - Re-initializing MAC

Downstream Bonded Channels
Channel Lock Status Modulation Channel ID Frequency Power SNR Correctables Uncorrectables
1 Locked QAM256 1 447000000 Hz 3.9 dBmV 40.1 dB 532 954
2 Locked QAM256 2 453000000 Hz 4.5 dBmV 40.2 dB 404 1076
3 Locked QAM256 3 459000000 Hz 4.8 dBmV 40.2 dB 421 933
4 Locked QAM256 4 465000000 Hz 4.5 dBmV 40.1 dB 533 994
5 Locked QAM256 5 471000000 Hz 4.2 dBmV 40 dB 602 1212
6 Locked QAM256 6 477000000 Hz 4.2 dBmV 40.1 dB 559 863
7 Locked QAM256 7 483000000 Hz 4.2 dBmV 40 dB 576 914
8 Locked QAM256 8 489000000 Hz 4.4 dBmV 39.9 dB 546 1015
9 Locked QAM256 9 495000000 Hz 4.3 dBmV 39.8 dB 564 984
10 Locked QAM256 10 507000000 Hz 3.3 dBmV 38.8 dB 687 966
11 Locked QAM256 11 513000000 Hz 3.2 dBmV 39.5 dB 678 888
12 Locked QAM256 12 519000000 Hz 3.4 dBmV 39.5 dB 695 962
13 Locked QAM256 13 525000000 Hz 3.5 dBmV 39.5 dB 723 862
14 Locked QAM256 14 531000000 Hz 3.3 dBmV 39.3 dB 811 845
15 Locked QAM256 15 537000000 Hz 2.6 dBmV 39.1 dB 802 798
16 Locked QAM256 16 543000000 Hz 2 dBmV 38.9 dB 894 730
 
Upstream Bonded Channels (Partial Service)
Channel Lock Status US Channel Type Channel ID Symbol Rate Frequency Power
1 Not Locked Unknown 4 0 Ksym/sec 16400000 Hz 0.0 dBmV
2 Locked ATDMA 1 5120 Ksym/sec 35600000 Hz 44.3 dBmV
3 Locked ATDMA 2 5120 Ksym/sec 29200000 Hz 45.3 dBmV
4 Locked ATDMA 3 5120 Ksym/sec 22800000 Hz 41.8 dBmV

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XfinityJoeTru

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7K Messages

Thanks for your review and escalation, @EG!

We appreciate you visiting and posting on our Forums, user_b8b6f4. I can assist with further troubleshooting your intermittent connectivity issues. As EG stated, I'd like to start with performing an advanced diagnostics on signal reaching and returning from your modem. I will also review your local Node / Plant health for errors or degradation. To get started,  please send us a peer to peer chat message with your full name and service address to Xfinity Support. To do so, you'll need to sign into the Forums if you are not. Then you'll need to locate and click on the peer to peer "Chat" Icon located in the upper right corner of this page. Next, click the "New Message" (paper & pencil) icon and type "Xfinity Support" in the to line and select "Xfinity Support" from the drop-down list. You can proceed to type your message in the text area near the bottom, and press enter to send the message. Please let me know if you have any questions.

I am an Official Xfinity Employee.
Official Employees are from multiple teams within Xfinity: CARE, Product, Leadership.
We ask that you post publicly so people with similar questions may benefit from the conversation.
Was your question answered? Please, mark a reply as the Accepted Answer.tick

4 years ago

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EG

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110.3K Messages

My pleasure @ComcastJoeTru !

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.

Was your question answered? Please mark an Accepted Answer!tick

4 years ago

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user_b8b6f4

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4 Messages

Thanks for the support @ComcastJoeTru - I have initiated the communication. Thanks for helping move this conversation on the way to resolution! 

4 years ago

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EG

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110.3K Messages

4 years ago

The signal stats are o/k but the error log entries indicate that something is going on. Perhaps there is noise ingress into the line(s) /  an upstream channel-return path impairment 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 will be able to poll the CMTS to see whether or not everything is in the green zone, see your node / cable plant and modem health, and also see a history plot for the modem. You should get a reply here in your topic. Good luck !

4

user_b8b6f4

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@EG

Thanks for the support! I look forward to their reply.  

4 years ago

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EG

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Quite welcome !

..................................

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.

Was your question answered? Please mark an Accepted Answer!tick

4 years ago

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jobrien0125

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2 Messages

Hello,

Was there ever a reply or potential resolution? I have been having the same problem all summer.

Thank you,

Joe

4 years ago

0

EG

Expert

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110.3K Messages

@jobrien0125

Please create a new topic of your own here on this board detailing your issue. Thanks.  The original poster has not returned. 4 month old dead thread now being closed.
 

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.

Was your question answered? Please mark an Accepted Answer!tick

4 years ago

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