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T3 timeouts and only 1 upstream bonded channel.

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Frequent Visitor

T3 timeouts and only 1 upstream bonded channel.

Recently replaced my old modem with a Motorola MB8600 and I noticed in the logs I am getting constant T3 timeouts and I only have 1 upstream bonded channel. I believe the Pwr and SNR all look good but please correct me if I am wrong.

 

Thoughts?

 

 Startup Sequence
 

 

   
   Startup Step Status Comment
 

 



  
   Acquire Downstream Channel 699000000 Hz Locked
 

 


  
   Upstream Connection OK Operational
 

 


  
   Boot State OK Operational
 

 



  
   Configuration File OK  
 

 


  
   Security Enabled BPI+
 

 


  



   Connection Status
 

 

   
   System Up Time 0 days 00h:09m:46s  
 

 


  
   Network Access Allowed  
 

 


  



   Downstream Bonded Channels
 

 

 
 

 


  
   Channel Lock Status Modulation Channel ID Freq. (MHz) Pwr (dBmV) SNR (dB) Corrected Uncorrected
   1 Locked QAM256 47 699.0 0.4 40.9 0 0
   2 Locked QAM256 17 513.0 0.9 41.7 0 0
   3 Locked QAM256 18 519.0 0.8 41.6 0 0
   4 Locked QAM256 19 525.0 0.8 41.6 0 0
   5 Locked QAM256 20 531.0 0.8 41.5 0 0
   6 Locked QAM256 21 543.0 0.5 41.6 0 0
   7 Locked QAM256 22 549.0 0.2 41.6 0 0
   8 Locked QAM256 23 555.0 0.0 41.4 0 0
   9 Locked QAM256 24 561.0 0.0 41.1 0 0
   10 Locked QAM256 25 567.0 0.1 41.5 0 0
   11 Locked QAM256 26 573.0 0.0 41.4 0 0
   12 Locked QAM256 27 579.0 0.0 41.2 0 0
   13 Locked QAM256 28 585.0 0.1 41.1 0 0
   14 Locked QAM256 29 591.0 0.1 41.1 0 0
   15 Locked QAM256 30 597.0 0.5 41.2 0 0
   16 Locked QAM256 31 603.0 0.9 41.2 0 0
   17 Locked QAM256 32 609.0 1.0 41.2 0 0
   18 Locked QAM256 33 615.0 0.8 41.2 0 0
   19 Locked QAM256 34 621.0 0.8 41.2 0 0
   20 Locked QAM256 35 627.0 0.8 41.2 0 0
   21 Locked QAM256 36 633.0 0.8 41.1 0 0
   22 Locked QAM256 37 639.0 0.8 41.2 0 0
   23 Locked QAM256 38 645.0 0.5 41.1 0 0
   24 Locked QAM256 39 651.0 0.1 40.8 0 0
   25 Locked QAM256 40 657.0 0.1 41.0 0 0
   26 Locked QAM256 41 663.0 0.4 41.2 0 0
   27 Locked QAM256 42 669.0 0.4 41.1 0 0
   28 Locked QAM256 43 675.0 0.1 40.3 0 0
   29 Locked QAM256 44 681.0 0.0 40.9 0 0
   30 Locked QAM256 45 687.0 0.1 41.0 0 0
   31 Locked QAM256 46 693.0 0.0 40.9 0 0
   32 Locked OFDM PLC 48 850.0 -2.8 38.0 729529 0



   Upstream Bonded Channels
 

 

 
 

 


  
   Channel Lock Status Channel Type Channel ID Symb. Rate (Ksym/sec) Freq. (MHz) Pwr (dBmV)
   1 Not Locked SC-QAM 5 5120 17.3 39.5
   2 Not Locked SC-QAM 6 5120 23.7 38.0
   3 Not Locked SC-QAM 7 5120 30.3 38.8
   4 Locked SC-QAM 8 5120 36.7 44.8

 

  16:57:18
Wed Apr 1 2020 Critical (3) No Ranging Response received - T3 time-out;;CM-QOS=1.1;CM-VER=3.1;
16:57:18
Wed Apr 1 2020 Critical (3) Ranging Request Retries exhausted;;CM-QOS=1.1;CM-VER=3.1;
16:57:18
Wed Apr 1 2020 Critical (3) 16 consecutive T3 timeouts while trying to range on upstream channel 3;;CM-QOS=1.1;CM-VER=3.1;
16:57:22
Wed Apr 1 2020 Critical (3) No Ranging Response received - T3 time-out;;CM-QOS=1.1;CM-VER=3.1;
16:57:23
Wed Apr 1 2020 Notice (6) CM-STATUS message sent. Event Type Code: 7; Chan ID: 7; DSID: N/A; MAC Addr: N/A; OFDM/OFDMA Profile ID: N/A.;;CM-QOS=1.1;CM-VER=3.1;
16:57:26
Wed Apr 1 2020 Critical (3) No Ranging Response received - T3 time-out;;CM-QOS=1.1;CM-VER=3.1;
16:57:26
Wed Apr 1 2020 Critical (3) Ranging Request Retries exhausted;;CM-QOS=1.1;CM-VER=3.1;
16:57:26
Wed Apr 1 2020 Critical (3) 16 consecutive T3 timeouts while trying to range on upstream channel 1;;CM-QOS=1.1;CM-VER=3.1;
16:57:40
Wed Apr 1 2020 Critical (3) No Ranging Response received - T3 time-out;;CM-QOS=1.1;CM-VER=3.1;
16:57:46
Wed Apr 1 2020 Notice (6) CM-STATUS message sent. Event Type Code: 7; Chan ID: 5 7; DSID: N/A; MAC Addr: N/A; OFDM/OFDMA Profile ID: N/A.;;CM-QOS=1.1;CM-VER=3.1;
16:58:38
Wed Apr 1 2020 Critical (3) No Ranging Response received - T3 time-out;;CM-QOS=1.1;CM-VER=3.1;
Highlighted
Expert

Re: T3 timeouts and only 1 upstream bonded channel.

The stats looked o/k at that snapshot in time. Have you tried power-cycling the modem to see if it will lock on to more upstream channels ?



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Highlighted
Frequent Visitor

Re: T3 timeouts and only 1 upstream bonded channel.

I've painfully power-cycled, hard reset, pleaded with, etc with no such luck. Each time this whole process takes at least 20 minutes. Are T3 timeouts and the 1 bonded upstream channel related?

 

Since the stats look OK could this be a bad modem? 

 

Highlighted
Frequent Visitor

Re: T3 timeouts and only 1 upstream bonded channel.

Just for giggles I replaced the splitter from a balanced 4-way to an unbalanced 3-way (7, 7 and 3.5 to the modem) since I'm not using the 4th line. Here are the lates stats.. unfortunately still only 1 upstream channel locked. Is having only 1 upstream locked even an issue?

 

Startup Sequence
 

 

   
   Startup Step Status Comment
 

 



  
   Acquire Downstream Channel 699000000 Hz Locked
 

 


  
   Upstream Connection OK Operational
 

 


  
   Boot State OK Operational
 

 



  
   Configuration File OK  
 

 


  
   Security Enabled BPI+
 

 


  



   Connection Status
 

 

   
   System Up Time 0 days 00h:13m:57s  
 

 


  
   Network Access Allowed  
 

 


  



   Downstream Bonded Channels
 

 

 
 

 


  
   Channel Lock Status Modulation Channel ID Freq. (MHz) Pwr (dBmV) SNR (dB) Corrected Uncorrected
   1 Locked QAM256 47 699.0 5.3 40.8 0 0
   2 Locked QAM256 17 513.0 6.1 41.6 0 0
   3 Locked QAM256 18 519.0 5.9 41.6 0 0
   4 Locked QAM256 19 525.0 5.8 41.3 0 0
   5 Locked QAM256 20 531.0 5.8 41.3 0 0
   6 Locked QAM256 21 543.0 5.5 41.4 0 0
   7 Locked QAM256 22 549.0 5.3 41.3 0 0
   8 Locked QAM256 23 555.0 5.0 41.0 0 0
   9 Locked QAM256 24 561.0 5.0 41.2 0 0
   10 Locked QAM256 25 567.0 5.1 41.1 0 0
   11 Locked QAM256 26 573.0 5.1 41.2 0 0
   12 Locked QAM256 27 579.0 5.0 41.0 0 0
   13 Locked QAM256 28 585.0 5.0 40.9 0 0
   14 Locked QAM256 29 591.0 4.9 40.8 0 0
   15 Locked QAM256 30 597.0 5.3 40.9 0 0
   16 Locked QAM256 31 603.0 5.6 41.1 0 0
   17 Locked QAM256 32 609.0 5.6 41.1 0 0
   18 Locked QAM256 33 615.0 5.5 40.9 0 0
   19 Locked QAM256 34 621.0 5.4 40.6 1 0
   20 Locked QAM256 35 627.0 5.4 41.0 0 0
   21 Locked QAM256 36 633.0 5.3 40.9 1 0
   22 Locked QAM256 37 639.0 5.2 41.1 0 0
   23 Locked QAM256 38 645.0 5.0 40.9 0 0
   24 Locked QAM256 39 651.0 4.5 40.7 1 0
   25 Locked QAM256 40 657.0 4.5 40.8 0 0
   26 Locked QAM256 41 663.0 5.1 40.8 0 0
   27 Locked QAM256 42 669.0 5.1 40.8 1 0
   28 Locked QAM256 43 675.0 4.9 40.6 0 0
   29 Locked QAM256 44 681.0 4.8 40.6 0 0
   30 Locked QAM256 45 687.0 4.9 40.7 2 0
   31 Locked QAM256 46 693.0 4.9 40.6 2 0
   32 Locked OFDM PLC 48 850.0 2.9 38.2 4452325 0



   Upstream Bonded Channels
 

 

 
 

 


  
   Channel Lock Status Channel Type Channel ID Symb. Rate (Ksym/sec) Freq. (MHz) Pwr (dBmV)
   1 Not Locked SC-QAM 5 5120 17.3 38.3
   2 Not Locked SC-QAM 6 5120 23.7 39.0
   3 Not Locked SC-QAM 7 5120 30.3 39.0
   4 Locked SC-QAM 8 5120 36.7 40.5

 

Highlighted
Frequent Visitor

Re: T3 timeouts and only 1 upstream bonded channel.

I also noticed that the Pwr on the non-locked upstream channels keeps oscilating between mid 30's to upper 30's. Not sure if there is anything to that?

 

  Upstream Bonded Channels
 

 

 
 

 


  
   Channel Lock Status Channel Type Channel ID Symb. Rate (Ksym/sec) Freq. (MHz) Pwr (dBmV)
   1 Not Locked SC-QAM 5 5120 17.3 35.3
   2 Not Locked SC-QAM 6 5120 23.7 34.5
   3 Not Locked SC-QAM 7 5120 30.3 35.3
   4 Locked SC-QAM 8 5120 36.7 40.5
Highlighted
Frequent Visitor

Re: T3 timeouts and only 1 upstream bonded channel.

@EG I have the same modem, 4 bonded locked upstream channel, and having T3 timeouts daily. 

10%-15% packet loss when I do a ping and do "internet speed test" 

Packet loss increases when I start to do video calls.

 

Comcast technician said as long as the packet loss not above 50%, there is no much they can do.

Anything in your experience, I can check on my side?