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T3 timeouts, Aborted responses, and intermittent internet

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Frequent Visitor

T3 timeouts, Aborted responses, and intermittent internet

Hello,

 

We have been having constant interruptions to our internet service that last anywhere from a few minutes to several hours, approximately 10-12 times per day. This is causing us problems working from home. Called Xfinity several times but they all keep saying "just monitor the situation."

 

Greatly appreciate any help.

 

Output from modem (Motorola MB7621):

 

Downstream Bonded Channels
 

 

 
 

 


  
   Channel Lock Status Modulation Channel ID Freq. (MHz) Pwr (dBmV) SNR (dB) Corrected Uncorrected
1 Locked QAM256 21 555.0 -8.2 37.9 49 178
2 Locked QAM256 1 417.0 -9.4 38.7 94 204
3 Locked QAM256 2 423.0 -9.2 38.8 143 101
4 Locked QAM256 3 429.0 -9.3 38.7 120 84
5 Locked QAM256 4 435.0 -9.2 38.7 93 174
6 Locked QAM256 5 453.0 -8.6 38.7 104 118
7 Locked QAM256 6 459.0 -8.4 38.8 138 161
8 Locked QAM256 7 465.0 -8.4 38.7 151 85
9 Locked QAM256 8 471.0 -8.2 37.4 70 163
10 Locked QAM256 9 477.0 -8.4 38.6 89 108
11 Locked QAM256 10 483.0 -8.3 38.3 99 300
12 Locked QAM256 11 489.0 -8.4 38.5 99 52
13 Locked QAM256 12 495.0 -8.1 38.6 66 163
14 Locked QAM256 13 507.0 -8.1 35.6 118 180
15 Locked QAM256 14 513.0 -8.0 37.8 121 27
16 Locked QAM256 15 519.0 -8.1 38.2 53 1
17 Locked QAM256 16 525.0 -8.4 32.8 83 123
18 Locked QAM256 17 531.0 -8.8 35.1 75 94
19 Locked QAM256 18 537.0 -8.6 37.4 62 91
20 Locked QAM256 19 543.0 -8.6 37.6 63 91
21 Locked QAM256 20 549.0 -8.4 38.3 58 83
22 Locked QAM256 22 561.0 -8.4 38.4 75 58
23 Locked QAM256 23 567.0 -8.3 38.3 39 49
24 Locked QAM256 24 573.0 -8.4 38.2 52 57
Total             2114 2745



 Time   Priority   Description 
 Time Not Established   Critical (3)   Unicast Ranging Received Abort Response - Re-initializing MAC;CM-MAC=00:40:36:69:db:78;CMTS-MAC=58:97:bd:98:5c:e9;CM-QOS=1.0;CM-VER=3.0; 
 Time Not Established   Critical (3)   No Ranging Response received - T3 time-out;CM-MAC=00:40:36:69:db:78;CMTS-MAC=58:97:bd:98:5c:e9;CM-QOS=1.0;CM-VER=3.0; 
 Time Not Established   Critical (3)   Unicast Ranging Received Abort Response - Re-initializing MAC;CM-MAC=00:40:36:69:db:78;CMTS-MAC=58:97:bd:98:5c:e9;CM-QOS=1.0;CM-VER=3.0; 
 Time Not Established   Critical (3)   No Ranging Response received - T3 time-out;CM-MAC=00:40:36:69:db:78;CMTS-MAC=58:97:bd:98:5c:e9;CM-QOS=1.0;CM-VER=3.0; 
 Time Not Established   Critical (3)   Unicast Ranging Received Abort Response - Re-initializing MAC;CM-MAC=00:40:36:69:db:78;CMTS-MAC=58:97:bd:98:5c:e9;CM-QOS=1.0;CM-VER=3.0; 
 Time Not Established   Critical (3)   No Ranging Response received - T3 time-out;CM-MAC=00:40:36:69:db:78;CMTS-MAC=58:97:bd:98:5c:e9;CM-QOS=1.0;CM-VER=3.0; 
 Time Not Established   Critical (3)   Unicast Ranging Received Abort Response - Re-initializing MAC;CM-MAC=00:40:36:69:db:78;CMTS-MAC=58:97:bd:98:5c:e9;CM-QOS=1.0;CM-VER=3.0; 
 Time Not Established   Critical (3)   No Ranging Response received - T3 time-out;CM-MAC=00:40:36:69:db:78;CMTS-MAC=58:97:bd:98:5c:e9;CM-QOS=1.0;CM-VER=3.0; 
 Time Not Established   Critical (3)   Unicast Ranging Received Abort Response - Re-initializing MAC;CM-MAC=00:40:36:69:db:78;CMTS-MAC=58:97:bd:98:5c:e9;CM-QOS=1.0;CM-VER=3.0; 
 Time Not Established   Critical (3)   No Ranging Response received - T3 time-out;CM-MAC=00:40:36:69:db:78;CMTS-MAC=58:97:bd:98:5c:e9;CM-QOS=1.0;CM-VER=3.0; 
 Time Not Established   Critical (3)   Unicast Ranging Received Abort Response - Re-initializing MAC;CM-MAC=00:40:36:69:db:78;CMTS-MAC=58:97:bd:98:5c:e9;CM-QOS=1.0;CM-VER=3.0; 
 Time Not Established   Critical (3)   No Ranging Response received - T3 time-out;CM-MAC=00:40:36:69:db:78;CMTS-MAC=58:97:bd:98:5c:e9;CM-QOS=1.0;CM-VER=3.0; 
 Time Not Established   Critical (3)   Unicast Ranging Received Abort Response - Re-initializing MAC;CM-MAC=00:40:36:69:db:78;CMTS-MAC=58:97:bd:98:5c:e9;CM-QOS=1.0;CM-VER=3.0; 
 Time Not Established   Critical (3)   SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=00:40:36:69:db:78;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.0;CM-VER=3.0; 
 Time Not Established   Critical (3)   Unicast Ranging Received Abort Response - Re-initializing MAC;CM-MAC=00:40:36:69:db:78;CMTS-MAC=58:97:bd:98:5c:e9;CM-QOS=1.0;CM-VER=3.0; 
 Time Not Established   Critical (3)   No Ranging Response received - T3 time-out;CM-MAC=00:40:36:69:db:78;CMTS-MAC=58:97:bd:98:5c:e9;CM-QOS=1.0;CM-VER=3.0; 
 Time Not Established   Critical (3)   Unicast Ranging Received Abort Response - Re-initializing MAC;CM-MAC=00:40:36:69:db:78;CMTS-MAC=58:97:bd:98:5c:e9;CM-QOS=1.0;CM-VER=3.0; 
 Time Not Established   Critical (3)   No Ranging Response received - T3 time-out;CM-MAC=00:40:36:69:db:78;CMTS-MAC=58:97:bd:98:5c:e9;CM-QOS=1.0;CM-VER=3.0; 
 Time Not Established   Critical (3)   Unicast Ranging Received Abort Response - Re-initializing MAC;CM-MAC=00:40:36:69:db:78;CMTS-MAC=58:97:bd:98:5c:e9;CM-QOS=1.0;CM-VER=3.0; 
 Time Not Established   Critical (3)   No Ranging Response received - T3 time-out;CM-MAC=00:40:36:69:db:78;CMTS-MAC=58:97:bd:98:5c:e9;CM-QOS=1.0;CM-VER=3.0; 
 Time Not Established   Notice (6)   Honoring MDD; IP provisioning mode = IPv6 
 Mon Jul 20 08:50:06 2020    Critical (3)   Unicast Ranging Received Abort Response - Re-initializing MAC;CM-MAC=00:40:36:69:db:78;CMTS-MAC=58:97:bd:98:5c:e9;CM-QOS=1.1;CM-VER=3.0; 
 Mon Jul 20 08:50:28 2020    Notice (6)   Honoring MDD; IP provisioning mode = IPv6 
 Mon Jul 20 09:24:55 2020    Critical (3)   Unicast Ranging Received Abort Response - Re-initializing MAC;CM-MAC=00:40:36:69:db:78;CMTS-MAC=58:97:bd:98:5c:e9;CM-QOS=1.1;CM-VER=3.0; 
 Mon Jul 20 09:25:29 2020    Critical (3)   Unicast Ranging Received Abort Response - Re-initializing MAC;CM-MAC=00:40:36:69:db:78;CMTS-MAC=58:97:bd:98:5c:e9;CM-QOS=1.0;CM-VER=3.0; 
 Mon Jul 20 09:25:50 2020    Critical (3)   No Ranging Response received - T3 time-out;CM-MAC=00:40:36:69:db:78;CMTS-MAC=58:97:bd:98:5c:e9;CM-QOS=1.0;CM-VER=3.0; 
 Mon Jul 20 09:26:14 2020    Critical (3)   Unicast Ranging Received Abort Response - Re-initializing MAC;CM-MAC=00:40:36:69:db:78;CMTS-MAC=58:97:bd:98:5c:e9;CM-QOS=1.0;CM-VER=3.0; 
 Mon Jul 20 09:26:25 2020    Critical (3)   No Ranging Response received - T3 time-out;CM-MAC=00:40:36:69:db:78;CMTS-MAC=58:97:bd:98:5c:e9;CM-QOS=1.0;CM-VER=3.0; 
 Mon Jul 20 09:26:48 2020    Critical (3)   Unicast Ranging Received Abort Response - Re-initializing MAC;CM-MAC=00:40:36:69:db:78;CMTS-MAC=58:97:bd:98:5c:e9;CM-QOS=1.0;CM-VER=3.0; 
 Mon Jul 20 09:27:48 2020    Critical (3)   No Ranging Response received - T3 time-out;CM-MAC=00:40:36:69:db:78;CMTS-MAC=58:97:bd:98:5c:e9;CM-QOS=1.0;CM-VER=3.0; 
 Mon Jul 20 09:28:06 2020    Notice (6)   Honoring MDD; IP provisioning mode = IPv6 
 Mon Jul 20 09:29:27 2020    Warning (5)   Unicast DSID PSN startup error 
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Frequent Visitor

Re: T3 timeouts, Aborted responses, and intermittent internet

Here is the upstream channels:

 

Upstream Bonded Channels
 

 

 
 

 


  
   Channel Lock Status Channel Type Channel ID Symb. Rate (Ksym/sec) Freq. (MHz) Pwr (dBmV)
1 Locked ATDMA 4 5120 17.3 55.5
2 Not Locked Unknown 0 0 0 0.0
3 Not Locked Unknown 0 0 0 0.0
4 Not Locked Unknown 0 0 0 0.0
5 Not Locked Unknown 0 0 0 0.0
6 Not Locked Unknown 0 0 0 0.0
7 Not Locked Unknown 0 0 0 0.0
8 Not Locked Unknown 0 0 0 0.0
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Regular Visitor

Re: T3 timeouts, Aborted responses, and intermittent internet

Delete

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Expert

Re: T3 timeouts, Aborted responses, and intermittent internet

The upstream power is on is too high / out of spec. The downstream power is almost out of spec as well. That can cause random disconnects, spontaneous re-booting of the modem, speed, packet loss, latency problems, and the un-bonding of channels.

In a self troubleshooting effort to try to obtain better connectivity / more wiggle room, check to see if there are there any excess/unneeded coax cable splitters in the line leading to the modem that can be eliminated/re-configured. Any splitters that remain should be high quality and cable rated for 5-1002 MHz, bi-directional, and no gold colored garbage types like GE, RadioShack, RCA, Philips, Leviton, Magnavox, and Rocketfish from big box stores like Home Depot, Lowes, Target, Wal-Mart etc. Splitters should be swapped with known to be good / new ones to test

If there aren't any unneeded splitters that can be eliminated and if your coax wiring setup can't be reconfigured so that there is a single two way splitter connected directly off of the drop from the street/pole with one port feeding the modem and the other port feeding the rest of the house/equipment with additional splits as needed, and you've checked all the wiring and fittings for integrity and tightness and refresh them by taking them apart then check for and clean off any corrosion / oxidation on the center wire and put them back together again, then perhaps it's best to book a tech visit to investigate and correct.



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Frequent Visitor

Re: T3 timeouts, Aborted responses, and intermittent internet

Thanks, @EG . I've ordered another splitter to see if that's the problem. Will update asap with results. Thanks again.

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Expert

Re: T3 timeouts, Aborted responses, and intermittent internet

Quite welcome ! Good luck with it !



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Frequent Visitor

Re: T3 timeouts, Aborted responses, and intermittent internet

@EG -- Just wanted to close the loop. We removed 1 splitter from the network, replaced the splitter from the main coax cable into the house, and so far things are working without any problems. Glad it was a simple fix. Thanks for the help.

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Expert

Re: T3 timeouts, Aborted responses, and intermittent internet

For curiosity, what do the signal stats look like now ?



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Re: T3 timeouts, Aborted responses, and intermittent internet

@EG Here they are after 24 hours of being connected without any interruptions in service...

 

Downstream Bonded Channels
 

 

 
 

 


  
   ChannelLock StatusModulationChannel IDFreq. (MHz)Pwr (dBmV)SNR (dB)CorrectedUncorrected
1LockedQAM25621555.0-2.638.3413371
2LockedQAM2561417.0-3.939.111872088
3LockedQAM2562423.0-3.739.111321709
4LockedQAM2563429.0-3.539.110701547
5LockedQAM2564435.0-3.539.19061324
6LockedQAM2565453.0-2.739.28951422
7LockedQAM2566459.0-2.639.1890993
8LockedQAM2567465.0-2.739.0799682
9LockedQAM2568471.0-2.538.6895570
10LockedQAM2569477.0-2.738.9749764
11LockedQAM25610483.0-2.738.7755539
12LockedQAM25611489.0-2.838.8629554
13LockedQAM25612495.0-2.638.8687552
14LockedQAM25613507.0-2.736.2651454
15LockedQAM25614513.0-2.638.5408582
16LockedQAM25615519.0-2.638.5543497
17LockedQAM25616525.0-2.838.11265906
18LockedQAM25617531.0-3.138.6638665
19LockedQAM25618537.0-3.038.7521680
20LockedQAM25619543.0-3.038.7646454
21LockedQAM25620549.0-2.838.9592387
22LockedQAM25622561.0-3.038.7501303
23LockedQAM25623567.0-2.938.7620184
24LockedQAM25624573.0-2.938.6436288
Total      1782818515



   Upstream Bonded Channels
 

 

 
 

 


  
   ChannelLock StatusChannel TypeChannel IDSymb. Rate (Ksym/sec)Freq. (MHz)Pwr (dBmV)
1LockedATDMA4512017.349.0
2LockedATDMA1512036.547.5
3LockedATDMA2512030.148.8
4LockedATDMA3512023.749.3
5Not LockedUnknown0000.0
6Not LockedUnknown0000.0
7Not LockedUnknown0000.0
8Not LockedUnknown0000.0
Highlighted
Expert

Re: T3 timeouts, Aborted responses, and intermittent internet

The upstream power is still a bit on the high side. The preferred area is 40 to 45 dB. It may be ok if it holds stable. Bottom line. Live with it for a while and see if the problem returns. Good luck with it !



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