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Visitor

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4 Messages

Sat, May 14, 2022 12:41 AM

Multiple Short Internet Disconnects per Day

I've been having a recurring issue where my internet disconnects multiple times per day for 1-3minutes each time. Xfinity online support has ran tests multiple times and cannot find the problem. I have also had a tech come out who confirmed there was no issues that they could find, however the disconnects keep happening. I've seen a few other forum posts that suggest the upstream/downstream power may not be correct which could cause this, but no idea how to change that. Any help would be greatly appreciated. 

Contributor

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36 Messages

Hace 13 d

are you running a firewall or some kind of security software. This may be an issue to which you need to tell said software to trust connection. Otherwise I would replace the modem. You cannot change the upstream or down stream signal that is on Xfinity's end. I also ask if you have changed any cables or plugged something in new around your modem. 

EG

Expert

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93.7K Messages

Hace 12 d

Sure. It can be changed....

@yeon 

What do the modem's signal stats look like ? Try getting them here; http://192.168.100.1 or here http://10.0.0.1 

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.


What is the exact make and model number of the modem / gateway device ?

Is this a WiFi connection ?

Visitor

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4 Messages

@EG​  thanks for the reply! I copied info below but don't see any section for Singal to Noise Ratios. I am using a Motorola Model MB8611 modem and Asus RT-AXS82U router. I am hardwire connected to the router though (not on wifi). 

 Startup Sequence    
   Startup Step Status Comment

  
   Acquire Downstream Channel 573000000 Hz Locked
  
   Upstream Connection OK Operational
  
   Boot State OK Operational

  
   Configuration File OK
  
   Security Enabled BPI+
  


   Connection Status    
   System Up Time 0 days 04h:48m:43s  
  
   Network Access Allowed  
  


   Downstream Bonded Channels  
  
   Channel Lock Status Modulation Channel ID Freq. (MHz) Pwr (dBmV) SNR (dB) Corrected Uncorrected
   1 Locked QAM256 25 573.0 10.2 43.3 0 0
   2 Locked QAM256 14 507.0 11.4 44.0 0 0
   3 Locked QAM256 15 513.0 11.3 44.0 0 0
   4 Locked QAM256 16 519.0 11.4 44.0 0 0
   5 Locked QAM256 17 525.0 11.3 42.9 0 0
   6 Locked QAM256 18 531.0 11.2 43.9 0 0
   7 Locked QAM256 19 537.0 11.1 43.9 0 0
   8 Locked QAM256 20 543.0 11.1 43.9 0 0
   9 Locked QAM256 21 549.0 10.9 43.8 0 0
   10 Locked QAM256 22 555.0 10.8 43.6 0 0
   11 Locked QAM256 23 561.0 10.7 43.7 0 0
   12 Locked QAM256 24 567.0 10.4 43.5 0 0
   13 Locked QAM256 26 579.0 10.2 43.3 0 0
   14 Locked QAM256 27 585.0 10.0 43.0 0 0
   15 Locked QAM256 28 591.0 9.9 43.0 0 0
   16 Locked OFDM PLC 29 693.0 7.9 39.8 101220181 0
   17 Locked QAM256 30 597.0 9.6 42.9 0 0
   18 Locked QAM256 31 603.0 8.8 42.6 0 0
   19 Locked QAM256 32 609.0 8.9 42.7 0 0
   20 Locked QAM256 33 615.0 9.3 41.8 0 0
   21 Locked QAM256 34 621.0 9.4 42.7 0 0
   22 Locked QAM256 35 627.0 9.3 42.0 0 0
   23 Locked QAM256 36 633.0 9.4 40.2 0 0
   24 Locked QAM256 37 639.0 9.2 42.5 0 0
   25 Locked QAM256 38 645.0 9.3 42.7 0 0
   26 Locked QAM256 39 651.0 8.9 42.4 0 0
   27 Locked QAM256 40 657.0 8.7 41.7 0 0
   28 Locked QAM256 41 663.0 8.6 41.8 0 0
   29 Locked QAM256 42 669.0 8.6 42.0 0 0
   30 Locked QAM256 43 675.0 8.4 41.8 0 0
   31 Locked QAM256 44 681.0 7.9 41.7 0 0
   32 Locked QAM256 45 687.0 7.2 41.5 0 0


   Upstream Bonded Channels  
  
   Channel Lock Status Channel Type Channel ID Symb. Rate (Ksym/sec) Freq. (MHz) Pwr (dBmV)
   1 Locked SC-QAM 61 5120 36.5 47.3
   2 Locked SC-QAM 62 5120 30.1 47.5
   3 Locked SC-QAM 63 5120 23.7 47.5
   4 Locked SC-QAM 64 5120 17.3 47.5
EG

Expert

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93.7K Messages

Hace 12 d

The SNR's are there in a column and they are good. Are there any modem RF error log entries being shown ? If so, please post them as well in their entirety (copy and paste them, don't post a screenshot) but redact the CM MAC and the CMTS MAC addresses for your privacy. They are considered to be personal information. Personally identifying information is a violation of their forum guidelines. The forum bot will not allow your post to be seen publically.

Visitor

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4 Messages

@EG​ Thanks for your help so far. Below is copy of the event log from the modem. I deleted out the MC MAC and CMTS MAC info. 

    Time Not Established   Critical (3)   No Ranging Response received - T3 time-out;1;
    Time Not Established   Critical (3)   SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;
    Time Not Established   Critical (3)   No Ranging Response received - T3 time-out;
    Time Not Established   Critical (3)   SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;
    Time Not Established   Critical (3)   No Ranging Response received - T3 time-out;
    Time Not Established   Critical (3)   SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;
    Time Not Established   Critical (3)   No Ranging Response received - T3 time-out;
    Time Not Established   Critical (3)   SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;
    Time Not Established   Critical (3)   No Ranging Response received - T3 time-out;
    Time Not Established   Critical (3)   SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;
    Time Not Established   Critical (3)   No Ranging Response received - T3 time-out;
    Time Not Established   Critical (3)   SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;
    Time Not Established   Critical (3)   No Ranging Response received - T3 time-out;
    Time Not Established   Critical (3)   SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;
    Time Not Established   Critical (3)   No Ranging Response received - T3 time-out;
    Time Not Established   Critical (3)   SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;
    Time Not Established   Critical (3)   No Ranging Response received - T3 time-out;
    Time Not Established   Critical (3)   SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;
    Time Not Established   Critical (3)   No Ranging Response received - T3 time-out
    Time Not Established   Critical (3)   SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;
    Time Not Established   Critical (3)   No Ranging Response received - T3 time-out;
    Time Not Established   Critical (3)   SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;
    Time Not Established   Critical (3)   No Ranging Response received - T3 time-out;
    Time Not Established   Critical (3)   SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;
    Time Not Established   Critical (3)   No Ranging Response received - T3 time-out;
    Time Not Established   Critical (3)   SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;
    Time Not Established   Critical (3)   No Ranging Response received - T3 time-out;
    Time Not Established   Critical (3)   SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;
    Time Not Established   Critical (3)   No Ranging Response received - T3 time-out;
    Time Not Established   Notice (6)   Honoring MDD; IP provisioning mode = IPv6
    03:14:46
Sat May 14 2022
  Notice (6)   DS profile assignment change. DS Chan ID: 32; Previous Profile: ; New Profile: 1 2 3.;
    03:15:01
Sat May 14 2022
  Notice (6)   CM-STATUS message sent. Event Type Code: 24; Chan ID: 29; DSID: N/A; MAC Addr: N/A; OFDM/OFDMA Profile ID: 0.;
EG

Expert

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93.7K Messages

Hace 12 d

FWIW most of those error log entries are unhelpful and basically invalid because they have the "Time Not Established" date / time stamp, so they really can't be used for troubleshooting purposes. They are really only one single event but it makes the entries look a lot more numerous than they really are. Are there any more that don't say Time Not Established" ?

Visitor

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4 Messages

@EG​ Please see below which is the errors from today thus far. Hoping these are more helpful in being able to troubleshoot. Appreciate the help thus far. 

   05:04:27
Tue May 17 2022
  Notice (6)   DS profile assignment change. DS Chan ID: 32; Previous Profile: ; New Profile: 1 2 3.;
    05:04:43
Tue May 17 2022
  Notice (6)   CM-STATUS message sent. Event Type Code: 24; Chan ID: 29; DSID: N/A; MAC Addr: N/A; OFDM/OFDMA Profile ID: 0.;
    14:42:39
Tue May 17 2022
  Notice (6)   CM-STATUS message sent. Event Type Code: 16; Chan ID: 29; DSID: N/A; MAC Addr: N/A; OFDM/OFDMA Profile ID: 3.;
    14:43:06
Tue May 17 2022
  Notice (6)   CM-STATUS message sent. Event Type Code: 24; Chan ID: 29; DSID: N/A; MAC Addr: N/A; OFDM/OFDMA Profile ID: 0 3.;
    16:24:15
Tue May 17 2022
  Notice (6)   CM-STATUS message sent. Event Type Code: 16; Chan ID: 29; DSID: N/A; MAC Addr: N/A; OFDM/OFDMA Profile ID: 3.;
    16:24:39
Tue May 17 2022
  Notice (6)   CM-STATUS message sent. Event Type Code: 24; Chan ID: 29; DSID: N/A; MAC Addr: N/A; OFDM/OFDMA Profile ID: 0 3.;;
EG

Expert

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93.7K Messages

Hace 8 d

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 !

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