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Intermittent internet and then complete lose of connection.

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Regular Visitor

Intermittent internet and then complete lose of connection.

After a day of high winds on the 14th, our internet connection was intermittent that night.  We were eventually able to watch streaming video.  Our connection was better all day on the 15th dispite continuing high winds.  Night time brought rain, sleet and continued high winds.  This time internet connection was completely lost.  The modem was unplugged and reconnected as advised.  It attempted reconnection all night.  Below is a snapshot of what was happening all night.  Connection wasn't reestablished until this morning, the 16th, after the sun was up.  Am I going to have problems with connection from now on due to wind and rain?  I attempted to report/correct the phone using my cell phone and the online assistant.  Nothing was discovered or corrected.

 

Mon Nov 16 05:07:18 2020Critical (3)TFTP failed - Request sent - No Response;CM-MAC=f8:a0:97:b6:3f:5c;CMTS-MAC=00:01:5c:b3:b2:90;CM-QOS=1.1;CM-VER=3.0;
Mon Nov 16 05:07:18 2020Critical (3)TFTP Request Retries exceeded, CM unable to register
Mon Nov 16 05:07:38 2020Critical (3)No UCDs Received - Timeout;;CM-MAC=f8:a0:97:b6:3f:5c;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.0;CM-VER=3.0;
Mon Nov 16 05:07:43 2020Critical (3)No Ranging Response received - T3 time-out
Mon Nov 16 05:08:00 2020Critical (3)TLV-11 - Illegal Set operation failed;CM-MAC=f8:a0:97:b6:3f:5c;CMTS-MAC=00:01:5c:b3:b2:90;CM-QOS=1.1;CM-VER=3.0;
Mon Nov 16 05:11:41 2020Critical (3)TFTP failed - Request sent - No Response;CM-MAC=f8:a0:97:b6:3f:5c;CMTS-MAC=00:01:5c:b3:b2:90;CM-QOS=1.1;CM-VER=3.0;
Mon Nov 16 05:11:41 2020Critical (3)TFTP Request Retries exceeded, CM unable to register
Mon Nov 16 05:11:44 2020Critical (3)SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=f8:a0:97:b6:3f:5c;CMTS-MAC=00:01:5c:b3:b2:90;CM-QOS=1.0;CM-VER=3.0;
Mon Nov 16 05:11:45 2020Critical (3)SYNC Timing Synchronization failure - Failed to acquire FEC framing;CM-MAC=f8:a0:97:b6:3f:5c;CMTS-MAC=00:01:5c:b3:b2:90;CM-QOS=1.0;CM-VER=3.0;
Mon Nov 16 05:11:51 2020Critical (3)SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=f8:a0:97:b6:3f:5c;CMTS-MAC=00:01:5c:b3:b2:90;CM-QOS=1.0;CM-VER=3.0;
Mon Nov 16 05:11:52 2020Critical (3)SYNC Timing Synchronization failure - Failed to acquire FEC framing;CM-MAC=f8:a0:97:b6:3f:5c;CMTS-MAC=00:01:5c:b3:b2:90;CM-QOS=1.0;CM-VER=3.0;
Mon Nov 16 05:11:57 2020Critical (3)SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=f8:a0:97:b6:3f:5c;CMTS-MAC=00:01:5c:b3:b2:90;CM-QOS=1.0;CM-VER=3.0;
Mon Nov 16 05:12:04 2020Critical (3)No Ranging Response received - T3 time-out
Mon Nov 16 05:12:22 2020Critical (3)TLV-11 - Illegal Set operation failed;CM-MAC=f8:a0:97:b6:3f:5c;CMTS-MAC=00:01:5c:b3:b2:90;CM-QOS=1.1;CM-VER=3.0;
Mon Nov 16 05:16:03 2020Critical (3)TFTP failed - Request sent - No Response;CM-MAC=f8:a0:97:b6:3f:5c;CMTS-MAC=00:01:5c:b3:b2:90;CM-QOS=1.1;CM-VER=3.0;
Mon Nov 16 05:16:03 2020Critical (3)TFTP Request Retries exceeded, CM unable to register
Mon Nov 16 05:16:10 2020Critical (3)SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=f8:a0:97:b6:3f:5c;CMTS-MAC=00:01:5c:b3:b2:90;CM-QOS=1.0;CM-VER=3.0;
Mon Nov 16 05:16:23 2020Critical (3)SYNC Timing Synchronization failure - Failed to acquire FEC framing;CM-MAC=f8:a0:97:b6:3f:5c;CMTS-MAC=00:01:5c:b3:b2:90;CM-QOS=1.0;CM-VER=3.0;
Mon Nov 16 05:16:30 2020Critical (3)No Ranging Response received - T3 time-out
Mon Nov 16 05:16:49 2020Critical (3)TLV-11 - Illegal Set operation failed;CM-MAC=f8:a0:97:b6:3f:5c;CMTS-MAC=00:01:5c:b3:b2:90;CM-QOS=1.1;CM-VER=3.0;
Mon Nov 16 05:20:31 2020Critical (3)TFTP failed - Request sent - No Response;CM-MAC=f8:a0:97:b6:3f:5c;CMTS-MAC=00:01:5c:b3:b2:90;CM-QOS=1.1;CM-VER=3.0;
Mon Nov 16 05:20:31 2020Critical (3)TFTP Request Retries exceeded, CM unable to register
Mon Nov 16 05:20:35 2020Critical (3)SYNC Timing Synchronization failure - Failed to acquire FEC framing;CM-MAC=f8:a0:97:b6:3f:5c;CMTS-MAC=00:01:5c:b3:b2:90;CM-QOS=1.0;CM-VER=3.0;
Mon Nov 16 05:20:41 2020Critical (3)SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=f8:a0:97:b6:3f:5c;CMTS-MAC=00:01:5c:b3:b2:90;CM-QOS=1.0;CM-VER=3.0;
Mon Nov 16 05:20:42 2020Critical (3)SYNC Timing Synchronization failure - Failed to acquire FEC framing;CM-MAC=f8:a0:97:b6:3f:5c;CMTS-MAC=00:01:5c:b3:b2:90;CM-QOS=1.0;CM-VER=3.0;
Mon Nov 16 05:20:47 2020Critical (3)SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=f8:a0:97:b6:3f:5c;CMTS-MAC=00:01:5c:b3:b2:90;CM-QOS=1.0;CM-VER=3.0;
Mon Nov 16 05:20:54 2020Critical (3)No Ranging Response received - T3 time-out
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Gold Problem Solver

Re: Intermittent internet and then complete lose of connection.

If you want to troubleshoot this yourself, please see Internet Troubleshooting Tips. If you still need help, please post the following information from your modem or gateway:

  • model number
  • downstream power levels and SNR
  • upstream power levels

If you can't find the problem or you'd rather have Comcast take care of it, call them at the phone number on your bill or 1-800-Comcast, or use one of the options on https://www.xfinity.com/support/contact-us/. If they can't fix the problem remotely (unlikely), insist they send a tech out to identify the cause and correct it.

If the tech finds bad coax, splitters, amplifiers, or connections in your home (even if Comcast originally supplied them) you'll probably have to pay for the visit unless you have their Service Protection Plan (https://www.xfinity.com/support/articles/service-protection-plan, closed to customers that don't already have it). If the trouble is due to a faulty Comcast rental device or anything outside your home you shouldn't be charged.