U

Visitor

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1 Message

Tue, Aug 2, 2022 10:58 AM

Intermittent Connection Interruption

Hello,

I recently set up my system and have been experiencing repeated temporary losses of connection (this includes both wireless and hardwired Ethernet connections).  During the workday, I would estimate about 3-5 interruptions.

Looking at the logs, I'm seeing repeated "No Ranging Response received - T3 time-out" and "SYNC Timing Synchronization failure". Reviewing the troubleshooting tips, I didn't immediately see anything that stood out, but please let me know if I missed something.

The log below is just from overnight after I sent a reset command in the evening:

Time Not Established   Critical (3)   SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=XX;CMTS-MAC=XX;CM-QOS=1.1;CM-VER=3.1;
Time Not Established Critical (3) No Ranging Response received - T3 time-out;CM-MAC=XX;CMTS-MAC=XX;CM-QOS=1.1;CM-VER=3.1;
Time Not Established   Critical (3)   SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=XX;CMTS-MAC=XX;CM-QOS=1.1;CM-VER=3.1;
Time Not Established Critical (3) No Ranging Response received - T3 time-out;CM-MAC=XX;CMTS-MAC=XX;CM-QOS=1.1;CM-VER=3.1;
Time Not Established   Critical (3)   SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=XX;CMTS-MAC=XX;CM-QOS=1.1;CM-VER=3.1;
Time Not Established Critical (3) No Ranging Response received - T3 time-out;CM-MAC=XX;CMTS-MAC=XX;CM-QOS=1.1;CM-VER=3.1;
Time Not Established   Critical (3)   SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=XX;CMTS-MAC=XX;CM-QOS=1.1;CM-VER=3.1;
Time Not Established Critical (3) No Ranging Response received - T3 time-out;CM-MAC=XX;CMTS-MAC=XX;CM-QOS=1.1;CM-VER=3.1;
Time Not Established   Notice (6)   Honoring MDD; IP provisioning mode = IPv6
5:01:10 Notice (6) DS profile assignment change. DS Chan ID: 32; Previous Profile: ; New Profile: 1 2 3.;CM-MAC=XX;CMTS-MAC=XX;CM-QOS=1.1;CM-VER=3.1;
Tue Aug 2 2022
5:01:29   Notice (6)   CM-STATUS message sent. Event Type Code: 24; Chan ID: 37; DSID: N/A; MAC Addr: N/A; OFDM/OFDMA Profile ID: 0.;CM-MAC=XX;CMTS-MAC=XX;CM-QOS=1.1;CM-VER=3.1;
Tue Aug 2 2022

Downstream:

   Channel Lock Status Modulation Channel ID Freq. (MHz) Pwr (dBmV) SNR (dB) Corrected Uncorrected
   1 Locked QAM256 5 507 4 44 0 0
   2 Locked QAM256 2 489 4.3 44.1 0 0
   3 Locked QAM256 3 495 4.2 44.1 0 0
   4 Locked QAM256 4 501 4 44 0 0
   5 Locked QAM256 6 513 4 43.8 0 0
   6 Locked QAM256 7 519 4.2 43.9 0 0
   7 Locked QAM256 8 525 4.4 44 0 0
   8 Locked QAM256 9 531 4.3 43.9 0 0
   9 Locked QAM256 10 537 3.9 43.6 0 0
   10 Locked QAM256 11 543 3.6 43.5 0 0
   11 Locked QAM256 12 549 4.1 43.7 0 0
   12 Locked QAM256 13 555 4.3 43.9 0 0
   13 Locked QAM256 14 561 4.1 43.7 0 0
   14 Locked QAM256 15 567 3.6 43.4 0 0
   15 Locked QAM256 16 573 3.4 43.3 0 0
   16 Locked QAM256 17 579 3.6 43.6 0 0
   17 Locked QAM256 18 585 3.4 43.4 0 0
   18 Locked QAM256 19 591 3 43 0 0
   19 Locked QAM256 20 597 3.3 43 0 0
   20 Locked QAM256 21 603 3.7 43.3 0 0
   21 Locked QAM256 22 609 3.7 43.4 0 0
   22 Locked QAM256 23 615 3.4 43.1 0 0
   23 Locked QAM256 24 621 3 42.9 0 0
   24 Locked QAM256 25 627 3.4 43.1 0 0
   25 Locked QAM256 26 633 3.7 43.4 0 0
   26 Locked QAM256 27 639 3.7 43.4 0 0
   27 Locked QAM256 28 645 3.5 43.2 0 0
   28 Locked QAM256 29 651 3.3 43.1 0 0
   29 Locked QAM256 30 657 3.7 43.4 0 0
   30 Locked QAM256 31 663 3.9 43.5 0 0
   31 Locked QAM256 32 669 4 43.5 0 0
   32 Locked OFDM PLC 37 690 4.2 43.3 3707046 0

Upstream:

   Channel Lock Status Channel Type Channel ID Symb. Rate (Ksym/sec) Freq. (MHz) Pwr (dBmV)
   1 Locked SC-QAM 1 5120 35.6 43.8
   2 Locked SC-QAM 2 5120 29.2 43.8
   3 Locked SC-QAM 3 5120 22.8 43
   4 Locked SC-QAM 4 5120 16.4 43.3
   5 Locked SC-QAM 5 1280 39.6 43.8
XfinityAmira

Official Employee

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2.8K Messages

2 m ago

Hello and thanks for taking the time to reach out to us on our Forums page. We're so thankful to have you as a customer, and it's upsetting to know you have been experiencing connection issues every day. We definitely know the importance of having a solid and steady connection, so I am sorry to hear that has not been the case for you. We appreciate you posting your modem logs, and we would love to take a further look into everything on our end. To best assist you with this further, please send us a Private Direct Message.

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