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Having intermittent signal, and upstream channels will not stay locked

Frequent Visitor

Having intermittent signal, and upstream channels will not stay locked

Startup Procedure
Procedure Status Comment
Acquire Downstream Channel 525000000 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 8 525000000 Hz 9.4 dBmV 37.8 dB 124 338
2 Locked QAM256 4 501000000 Hz 8.9 dBmV 38.1 dB 12 54
3 Locked QAM256 6 513000000 Hz 9 dBmV 37.9 dB 14 56
4 Locked QAM256 7 519000000 Hz 9.2 dBmV 37.9 dB 14 52
5 Locked QAM256 9 531000000 Hz 9.6 dBmV 37.9 dB 35 34
6 Locked QAM256 10 537000000 Hz 9.6 dBmV 37.9 dB 41 111
7 Locked QAM256 11 543000000 Hz 9.3 dBmV 37.7 dB 23 88
8 Locked QAM256 12 549000000 Hz 9.2 dBmV 37.6 dB 12 55
9 Locked QAM256 13 555000000 Hz 9.2 dBmV 37.5 dB 14 53
10 Locked QAM256 14 561000000 Hz 9.2 dBmV 37.5 dB 10 58
11 Locked QAM256 15 567000000 Hz 9.3 dBmV 37.2 dB 18 49
12 Locked QAM256 16 573000000 Hz 9.4 dBmV 37.4 dB 37 29
13 Locked QAM256 19 591000000 Hz 9.6 dBmV 37.3 dB 17 51
14 Locked QAM256 23 615000000 Hz 9 dBmV 37.1 dB 15 53
15 Locked QAM256 26 633000000 Hz 9.6 dBmV 37 dB 13 55
16 Locked QAM256 31 663000000 Hz 9.5 dBmV 36.5 dB 14 61
 
Upstream Bonded Channels
Channel Lock Status US Channel Type Channel ID Symbol Rate Frequency Power
1 Locked ATDMA 10 5120 Ksym/sec 28500000 Hz 39.5 dBmV
2 Locked ATDMA 9 5120 Ksym/sec 34900000 Hz 39.5 dBmV
3 Locked ATDMA 11 5120 Ksym/sec 22100000 Hz 39.8 dBmV
 
Current System Time:Sat Oct 27 20:24:12 2018
Frequent Visitor

Re: Having intermittent signal, and upstream channels will not stay locked

This shows the modem currently locked, but my network will go down, and I find that I will only have 1 locked channel

Frequent Visitor

Re: Having intermittent signal, and upstream channels will not stay locked

2018-10-27, 19:09:42 Critical (3) Received Response to Broadcast Maintenance Request, But no Unicast Maintenance opportunities received - T4 time out;CM-MAC=40:5d:82:3f:5e:58;CMTS-MAC=00:01:5c:63:04:6a;CM-QOS=1.1;CM-VER=3.0;
2018-10-27, 19:09:55 Notice (6) Honoring MDD; IP provisioning mode = IPv6
2018-10-27, 19:10:38 Warning (5) Dynamic Range Window violation
2018-10-27, 19:10:41 Critical (3) Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=40:5d:82:3f:5e:58;CMTS-MAC=00:01:5c:63:04:6a;CM-QOS=1.1;CM-VER=3.0;
2018-10-27, 19:13:50 Warning (5) Dynamic Range Window violation
2018-10-27, 19:18:13 Critical (3) Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=40:5d:82:3f:5e:58;CMTS-MAC=00:01:5c:63:04:6a;CM-QOS=1.1;CM-VER=3.0;
2018-10-27, 19:18:21 Warning (5) Dynamic Range Window violation
2018-10-27, 19:23:41 Critical (3) Received Response to Broadcast Maintenance Request, But no Unicast Maintenance opportunities received - T4 time out;CM-MAC=40:5d:82:3f:5e:58;CMTS-MAC=00:01:5c:63:04:6a;CM-QOS=1.1;CM-VER=3.0;
2018-10-27, 19:23:50 Critical (3) Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=40:5d:82:3f:5e:58;CMTS-MAC=00:01:5c:63:04:6a;CM-QOS=1.0;CM-VER=3.0;
2018-10-27, 19:23:56 Notice (6) Honoring MDD; IP provisioning mode = IPv6
2018-10-27, 19:46:50 Warning (5) Dynamic Range Window violation
2018-10-27, 19:46:52 Critical (3) Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=40:5d:82:3f:5e:58;CMTS-MAC=00:01:5c:63:04:6a;CM-QOS=1.1;CM-VER=3.0;
2018-10-27, 19:46:54 Warning (5) Dynamic Range Window violation
2018-10-27, 19:51:41 Critical (3) Received Response to Broadcast Maintenance Request, But no Unicast Maintenance opportunities received - T4 time out;CM-MAC=40:5d:82:3f:5e:58;CMTS-MAC=00:01:5c:63:04:6a;CM-QOS=1.1;CM-VER=3.0;
2018-10-27, 19:51:55 Notice (6) Honoring MDD; IP provisioning mode = IPv6
2018-10-27, 19:52:09 Critical (3) Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=40:5d:82:3f:5e:58;CMTS-MAC=00:01:5c:63:04:6a;CM-QOS=1.1;CM-VER=3.0;
2018-10-27, 19:52:10 Warning (5) Dynamic Range Window violation
Expert

Re: Having intermittent signal, and upstream channels will not stay locked


@Breathmetal wrote:

This shows the modem currently locked, but my network will go down, and I find that I will only have 1 locked channel


Is that only 1 *upstream* or 1 *downstream* channel ?



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Frequent Visitor

Re: Having intermittent signal, and upstream channels will not stay locked

1 upstream, sorry
Frequent Visitor

Re: Having intermittent signal, and upstream channels will not stay locked

Here is an example. Ill either have 1 or maybe 2 locked channels above 52.0 dBmV
pick me.png
Expert

Re: Having intermittent signal, and upstream channels will not stay locked

The upstream power is too high in that last screenshot ! Looks like you have an intermittent upstream / return path impairment problem going on. This is typically caused by noise ingress into the line(s) somewhere.  That can cause the un-bonding of channels.

 

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 try referring your topic to the resident Experts here who can then 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.



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Bronze Problem Solver

Re: Having intermittent signal, and upstream channels will not stay locked

Breathmetal -- I can check your levels going forward from here. To protect the privacy of your account, can you provide your full name exactly as it's listed on the billing statement? To send a private message click on my name, then click "Send a message".


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Frequent Visitor

Re: Having intermittent signal, and upstream channels will not stay locked

I did have a tech come out the other day and replace the outside line, as it was old and full of water. After replacing, I am seeing improved connection, but my connection is still dropping multiple times per day
Frequent Visitor

Re: Having intermittent signal, and upstream channels will not stay locked

Thanks for the help EG!
Bronze Problem Solver

Re: Having intermittent signal, and upstream channels will not stay locked

Thank you, can I ask who I'm speaking with now?


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Frequent Visitor

Re: Having intermittent signal, and upstream channels will not stay locked

The account owner that just messaged you
Frequent Visitor

Re: Having intermittent signal, and upstream channels will not stay locked

I had a tech out last week to replace the line going to my house. It helped a little, but I am still seeing 50+ dbmv on locked channels from time to time. My connection is dumping more frequently in the past 2 days. I am at a loss still
Gold Problem Solver

Re: Having intermittent signal, and upstream channels will not stay locked


@Breathmetal wrote: ... I am still seeing 50+ dbmv on locked channels from time to time. ...

Are you still getting "Dynamic Range Window violation" warnings in the error log? Those suggest an intermittent upstream connection.

Frequent Visitor

Re: Having intermittent signal, and upstream channels will not stay locked

Yes! Multiple times over. Again, I have 1 cable inside my home running directly to my modem. The tech inspected it and said the cable inside was fine. Outside cable running to my house was replaced. This is after that replacement as of today:
Capture+_2018-11-05-22-09-05.png
Frequent Visitor

Re: Having intermittent signal, and upstream channels will not stay locked

Any feedback @CCShane?
Expert

Re: Having intermittent signal, and upstream channels will not stay locked

I'm going to try to re-escalate your issue.



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Frequent Visitor

Re: Having intermittent signal, and upstream channels will not stay locked

@EG thanks!
Official Employee

Re: Having intermittent signal, and upstream channels will not stay locked

Breathmetal- 

 

Hello, I just responded back to your PM. Please continue talking with me there for further assistance. 


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Frequent Visitor

Re: Having intermittent signal, and upstream channels will not stay locked

@ComcastAlly is there any way to see if there are problems at the node? Is there anything I can do in the meantime before another tech has to come out?
Official Employee

Re: Having intermittent signal, and upstream channels will not stay locked

Breathmetal - 

 

I did check the node health and don't see any obvious issues. However, the technician would refer this to maintenance if they did find any issues outside. 


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Frequent Visitor

Re: Having intermittent signal, and upstream channels will not stay locked

Tech visit went very well!  Technician stated that there was a bent connector where the drop meets the pole. Connector was replaced and everything seems to be functioning as it should.  No new errors in the modem log in the last couple days, correctables are negligible, and no unccorectables.  All levels seem to be within range now.  Upstream levels are between 36-39dbmv now, and stay locked. 

Expert

Re: Having intermittent signal, and upstream channels will not stay locked

Glad that you got it straightened out ! Thanks for reporting back.


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Official Employee

Re: Having intermittent signal, and upstream channels will not stay locked

Breathmetal - 

 

I'm glad to hear that the technician was able to resolve the service issues. Please feel free to reach out again if you need any additional assistance. 


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