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Visitor

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6 Messages

Sunday, April 17th, 2022 3:29 PM

Closed

Ranging Request Retries exhausted

our connection is intermittently slow or the signal is weak on the radio. Event log on the modem is scrolling with this:

08:21:24
Sun Apr 17 2022
  Critical (3)   16 consecutive T3 timeouts while trying to range on upstream channel
    08:21:34
Sun Apr 17 2022
  Critical (3)   No Ranging Response received - T3 time-out;;
    08:21:34
Sun Apr 17 2022
  Critical (3)   Ranging Request Retries exhausted;

could this indicate a problem with the drop? or a config issue on the modem

Accepted Solution

Expert

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110.4K Messages

3 years ago

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 (Cable Modem Termination System) to check 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 and poll for those upstream receive signal stats.


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

Expert

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110.4K Messages

3 years ago

If this a with a WiFi connection, for a test, does a computer / device that is hardwired directly to the router / gateway device with an ethernet cable have the same problem ?


With this test, we are trying to isolate this down to being either a WiFi-only problem or a problem with the general connection to the Comcast system which would of course affect both. It's a good first step of troubleshooting before proceeding any further. 

Visitor

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6 Messages

@EG​ yes with a hardwired computer the log still scrolls with the same message

Expert

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110.4K Messages

3 years ago

Please redact all of the CM MAC and the CMTS MAC addresses in your error log entries for your privacy.  They are considered to be personal information. Personally identifiable information is a violation of their forum guidelines. The forum bot will not allow your post to be seen publically. It flagged your post as "Private".

Expert

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110.4K Messages

3 years ago

I was talking about the slowness problem as WiFi / LAN problems can not cause those error log messages. Only the WAN connection to the Comcast system can. That said. Please copy all of the text in its entirety of the *Downstream Power Levels*, the *SNR's* (Signal to Noise Ratios), and the *Upstream Power Level* numbers and paste them into your next post.

(edited)

Visitor

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6 Messages

@EG​ thanks @EG, this is logging every minute. I checked the cable out to the street, 200', and good quality cable with waterproof connectors on both ends going to a splitter bet our neighbor, all comcast. funny looking filter can coming out of the main service splitter that is maybe a filter for brodcast freqs?

12:03:18
Sun Apr 17 2022

 

Critical (3)

 

16 consecutive T3 timeouts while trying to range on upstream channel 1;CM-MAC=;CM-VER=3.1;

12:04:19
Sun Apr 17 2022

 

Critical (3)

 

No Ranging Response received - T3 time-out;CM-MAC=;CM-VER=3.1;

12:04:19
Sun Apr 17 2022

 

Critical (3)

 

Ranging Request Retries exhausted;CM-MAC=;CM-VER=3.1;

12:04:19
Sun Apr 17 2022

 

Critical (3)

 

16 consecutive T3 timeouts while trying to range on upstream channel 3;CM-MAC=;CM-VER=3.1;

12:04:36
Sun Apr 17 2022

 

Critical (3)

 

No Ranging Response received - T3 time-out;CM-MAC=;CM-VER=3.1;

12:04:36
Sun Apr 17 2022

 

Critical (3)

 

Ranging Request Retries exhausted;CM-MAC=;CM-VER=3.1;

12:04:36
Sun Apr 17 2022

 

Critical (3)

 

16 consecutive T3 timeouts while trying to range on upstream channel 4;CM-MAC=;CM-VER=3.1;

12:04:48
Sun Apr 17 2022

 

Critical (3)

 

No Ranging Response received - T3 time-out;CM-MAC=;CM-VER=3.1;

12:04:48
Sun Apr 17 2022

 

Critical (3)

 

Ranging Request Retries exhausted;CM-MAC=;CM-VER=3.1;

12:04:48
Sun Apr 17 2022

 

Critical (3)

 

16 consecutive T3 timeouts while trying to range on upstream channel 2;CM-MAC=;CM-VER=3.1;

12:04:53
Sun Apr 17 2022

 

Critical (3)

 

No Ranging Response received - T3 time-out;CM-MAC=;CM-VER=3.1;

12:04:53
Sun Apr 17 2022

 

Critical (3)

 

Ranging Request Retries exhausted;CM-MAC=;CM-QOS=1.1;CM-VER=3.1;

12:04:53
Sun Apr 17 2022

 

Critical (3)

 

16 consecutive T3 timeouts while trying to range on upstream channel 1;CM-MAC=0;CM-VER=3.1;

12:05:45
Sun Apr 17 2022

 

Critical (3)

 

No Ranging Response received - T3 time-out;CM-MAC=;CM-VER=3.1;

12:05:45
Sun Apr 17 2022

 

Critical (3)

 

Ranging Request Retries exhausted;CM-MAC=;CM-VER=3.1;

12:05:45
Sun Apr 17 2022

 

Critical (3)

 

16 consecutive T3 timeouts while trying to range on upstream channel 3;CM-MAC=0;CM-VER=3.1;

Visitor

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6 Messages

@user_e567b7

   Downstream Bonded Channels  
  
   Channel Lock Status Modulation Channel ID Freq. (MHz) Pwr (dBmV) SNR (dB) Corrected Uncorrected
   1 Locked QAM256 1 459.0 2.0 40.6 0 0
   2 Locked QAM256 2 465.0 1.9 40.7 1011 3245
   3 Locked QAM256 3 471.0 1.7 40.6 810 3229
   4 Locked QAM256 4 477.0 1.7 40.5 1822 4662
   5 Locked QAM256 5 483.0 1.8 40.5 294 1489
   6 Locked QAM256 6 489.0 1.8 40.5 1024 5480
   7 Locked QAM256 7 519.0 1.5 40.3 2040 7005
   8 Locked QAM256 8 525.0 1.7 40.4 410 1958
   9 Locked QAM256 9 531.0 1.7 40.5 301 1460
   10 Locked QAM256 10 537.0 1.6 40.4 331 1438
   11 Locked QAM256 11 543.0 2.1 40.7 313 1454
   12 Locked QAM256 12 549.0 1.8 40.5 282 1481
   13 Locked QAM256 13 555.0 1.4 40.4 287 1466
   14 Locked QAM256 14 561.0 1.6 40.3 0 0
   15 Locked QAM256 15 567.0 1.6 40.3 290 1477
   16 Locked QAM256 16 573.0 1.6 40.4 0 0
   17 Locked QAM256 17 579.0 1.9 40.5 316 1442
   18 Locked QAM256 18 585.0 1.9 40.5 3202 16033
   19 Locked QAM256 19 591.0 1.5 40.2 836 2826
   20 Locked QAM256 20 597.0 1.3 40.1 327 1450
   21 Locked QAM256 21 603.0 1.1 39.9 301 1469
   22 Locked QAM256 22 609.0 1.0 40.0 392 1986
   23 Locked QAM256 23 615.0 1.1 39.9 796 2963
   24 Locked QAM256 24 621.0 1.0 39.9 7901 27167
   25 Locked QAM256 25 627.0 0.8 39.9 4046 20691
   26 Locked QAM256 26 633.0 0.5 39.6 6303 22380
   27 Locked QAM256 27 639.0 0.3 39.5 6061 12856
   28 Locked QAM256 28 645.0 0.4 39.5 709 2449
   29 Locked QAM256 29 651.0 0.6 39.7 800 2343
   30 Locked QAM256 30 657.0 1.0 40.0 855 2583
   31 Locked QAM256 31 663.0 1.2 39.8 697 2073
   32 Locked QAM256 32 669.0 0.8 39.5 671 2198
   33 Locked OFDM PLC 159 805.0 2.1 39.7 27782263 1268

Upstream Bonded Channels  
  
   Channel Lock Status Channel Type Channel ID Symb. Rate (Ksym/sec) Freq. (MHz) Pwr (dBmV)
   1 Not Locked SC-QAM 1 2560 10.4 23.8
   2 Not Locked SC-QAM 2 5120 16.4 32.0
   3 Not Locked SC-QAM 3 5120 22.8 31.3
   4 Not Locked SC-QAM 4 5120 29.2 26.8
   5 Locked SC-QAM 5 5120 35.6 34.0
   6 Locked SC-QAM 6 2560 40.4 32.0

Problem Solver

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785 Messages

@user_e567b7 Thank you for reaching out and bring this to our attention. I can see how this would be frustrating. We would love to troubleshoot this for you. Could you please send our team a direct message with your full name and full address? Our team can most definitely take a further look at this issue.

 

To send a "Peer to peer" ("Private") message:

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• Press Enter to send it

I no longer work for Comcast.

Expert

 • 

110.4K Messages

3 years ago

@user_e567b7 

FWIW. You have an upstream channel / return path impairment of some sort / connection quality problem. There is an 11 dB difference in the signal power between some of the channels. There should be no more than a 3 dB or so difference. You may want to get a tech out to investigate and correct this. Good luck with it !

(edited)

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