Random Loss Of Service

[Justus30]

I've had about 4 outages that resulted in the loss of internet service for the last two weeks. 

They seem to last about 30 minutes each. I've confirmed my router is not the cause of the issue. Restarting the cable modem enough times seems to be what resolves the issue. I've already tried resetting it to factory defaults and the problem persist. 

I have a Netgear CM700 cable modem. I purchased it myself. During the outage, I looked at the comcast app to see if there was an outage in my area. Both times I didn't see anything.

Unplugging the cable modem seems to eventually sort out the issue. But the last few times it took a few tries. I'm not certain if restarting is what resulted in my connection working again.

I looked in the log on my cable modem and found the following. There seems to be something going on when the cable modem receiving its ranging information. I'm in an old apartment building and wondering if something is going on with the physical connection outside. This problem did seem to start during a day the temperature was hotter. I'm wondering if it might be an equipment malfunction.

Time	Priority	Description
Jul 26 2020 08:33:30	Critical (3)	No Ranging Response received - T3 time-out
Jul 26 2020 08:33:30	Critical (3)	No Ranging Response received - T3 time-out
Jul 26 2020 08:34:17	Critical (3)	Unicast Ranging Received Abort Response - initializing MAC
Jul 26 2020 08:34:18	Critical (3)	No Ranging Response received - T3 time-out
Time Not Established	Critical (3)	Unicast Ranging Received Abort Response - initializing MAC
Time Not Established	Critical (3)	No Ranging Response received - T3 time-out
Time Not Established	Critical (3)	Unicast Ranging Received Abort Response - initializing MAC
Time Not Established	Critical (3)	No Ranging Response received - T3 time-out
Time Not Established	Critical (3)	Unicast Ranging Received Abort Response - initializing MAC
Time Not Established	Critical (3)	No Ranging Response received - T3 time-out
Time Not Established	Critical (3)	Unicast Ranging Received Abort Response - initializing MAC
Time Not Established	Critical (3)	No Ranging Response received - T3 time-out
Time Not Established	Critical (3)	Unicast Ranging Received Abort Response - initializing MAC
Time Not Established	Critical (3)	No Ranging Response received - T3 time-out
Time Not Established	Critical (3)	Unicast Ranging Received Abort Response - initializing MAC
Time Not Established	Critical (3)	No Ranging Response received - T3 time-out
Time Not Established	Critical (3)	Unicast Ranging Received Abort Response - initializing MAC
Time Not Established	Critical (3)	No Ranging Response received - T3 time-out
Time Not Established	Critical (3)	Unicast Ranging Received Abort Response - initializing MAC
Time Not Established	Critical (3)	No Ranging Response received - T3 time-out
Time Not Established	Critical (3)	Unicast Ranging Received Abort Response - initializing MAC
Time Not Established	Critical (3)	No Ranging Response received - T3 time-out
Time Not Established	Critical (3)	Unicast Ranging Received Abort Response - initializing MAC
Time Not Established	Critical (3)	No Ranging Response received - T3 time-out
Time Not Established	Critical (3)	Unicast Ranging Received Abort Response - initializing MAC
Time Not Established	Critical (3)	No Ranging Response received - T3 time-out
Time Not Established	Critical (3)	Unicast Ranging Received Abort Response - initializing MAC
Time Not Established	Critical (3)	No Ranging Response received - T3 time-out
Time Not Established	Critical (3)	Unicast Ranging Received Abort Response - initializing MAC
Time Not Established	Critical (3)	No Ranging Response received - T3 time-out
Time Not Established	Critical (3)	Unicast Ranging Received Abort Response - initializing MAC
Time Not Established	Critical (3)	No Ranging Response received - T3 time-out
Time Not Established	Critical (3)	Unicast Ranging Received Abort Response - initializing MAC
Time Not Established	Critical (3)	No Ranging Response received - T3 time-out
Time Not Established	Critical (3)	Unicast Ranging Received Abort Response - initializing MAC
Time Not Established	Critical (3)	No Ranging Response received - T3 time-out
Time Not Established	Critical (3)	Unicast Ranging Received Abort Response - initializing MAC
Time Not Established	Critical (3)	No Ranging Response received - T3 time-out
Time Not Established	Critical (3)	Unicast Ranging Received Abort Response - initializing MAC
Time Not Established	Critical (3)	No Ranging Response received - T3 time-out
Jul 26 2020 09:35:33	Warning (5)	MIMO Event MIMO: Stored MIMO=-1 post cfg file MIMO=-1

[EG]

Please also post the *Downstream Power Level*, the *Upstream Power Level*, and the *SNR* (Signal to Noise Ratio) numbers.

[Justus30]

Downstream Bonded Channels

Channel Lock Status Modulation Channel ID Frequency Power SNR Correctables UnCorrectables 1 Locked QAM 256 5 483000000 Hz -4.5 dBmV 37.6 dB 1270 6645 2 Locked QAM 256 6 489000000 Hz -4.2 dBmV 37.3 dB 1238 7069 3 Locked QAM 256 7 495000000 Hz -4.2 dBmV 37.6 dB 991 6228 4 Locked QAM 256 8 507000000 Hz -4.0 dBmV 37.6 dB 1108 6936 5 Locked QAM 256 9 513000000 Hz -4.0 dBmV 37.6 dB 1168 6058 6 Locked QAM 256 10 519000000 Hz -4.0 dBmV 37.3 dB 1123 6338 7 Locked QAM 256 11 525000000 Hz -3.9 dBmV 37.3 dB 1602 6452 8 Locked QAM 256 12 531000000 Hz -3.9 dBmV 37.6 dB 1315 7197 9 Locked QAM 256 13 543000000 Hz -3.7 dBmV 37.6 dB 893 7391 10 Locked QAM 256 14 549000000 Hz -3.7 dBmV 37.3 dB 1262 6684 11 Locked QAM 256 15 555000000 Hz -3.7 dBmV 37.3 dB 1611 6600 12 Locked QAM 256 16 561000000 Hz -3.5 dBmV 37.3 dB 1192 7048 13 Locked QAM 256 17 567000000 Hz -3.5 dBmV 37.6 dB 1316 6952 14 Locked QAM 256 18 573000000 Hz -3.5 dBmV 37.6 dB 1053 7611 15 Locked QAM 256 19 579000000 Hz -3.5 dBmV 37.3 dB 1171 6154 16 Locked QAM 256 20 585000000 Hz -3.5 dBmV 37.6 dB 806 7564 17 Locked QAM 256 21 591000000 Hz -3.5 dBmV 37.6 dB 1040 7538 18 Locked QAM 256 22 597000000 Hz -3.5 dBmV 37.6 dB 956 6198 19 Locked QAM 256 23 603000000 Hz -3.5 dBmV 37.3 dB 1032 7295 20 Locked QAM 256 24 609000000 Hz -3.5 dBmV 37.6 dB 1158 6112 21 Locked QAM 256 25 615000000 Hz -3.5 dBmV 37.6 dB 922 5416 22 Locked QAM 256 26 621000000 Hz -3.5 dBmV 37.3 dB 922 7203 23 Locked QAM 256 27 627000000 Hz -3.5 dBmV 37.6 dB 811 6167 24 Locked QAM 256 28 633000000 Hz -3.4 dBmV 37.3 dB 1490 6778 25 Locked QAM 256 29 639000000 Hz -3.4 dBmV 37.3 dB 157 3483 26 Locked QAM 256 30 645000000 Hz -3.4 dBmV 37.3 dB 114 3225 27 Locked QAM 256 31 651000000 Hz -3.4 dBmV 37.9 dB 154 3348 28 Locked QAM 256 32 657000000 Hz -3.2 dBmV 37.6 dB 124 3289 29 Locked QAM 256 33 663000000 Hz -3.2 dBmV 37.6 dB 106 3305 30 Locked QAM 256 34 669000000 Hz -3.0 dBmV 37.6 dB 228 3293 31 Locked QAM 256 35 675000000 Hz -3.0 dBmV 37.3 dB 123 3284 32 Locked QAM 256 36 681000000 Hz -2.7 dBmV 37.9 dB 200 3379

Upstream Bonded Channels

Channel Lock Status US Channel Type Channel ID Symbol Rate Frequency Power 1 Locked ATDMA 3 5120 Ksym/sec 17300000 Hz 46.8 dBmV 2 Locked ATDMA 4 5120 Ksym/sec 23700000 Hz 46.5 dBmV 3 Locked ATDMA 1 5120 Ksym/sec 30100000 Hz 46.5 dBmV 4 Locked ATDMA 2 5120 Ksym/sec 36500000 Hz 47.0 dBmV 5 Not Locked N/A Unknown 0 Ksym/sec 0 Hz 0.0 dBmV 6 Not Locked N/A Unknown 0 Ksym/sec 0 Hz 0.0 dBmV 7 Not Locked N/A Unknown 0 Ksym/sec 0 Hz 0.0 dBmV 8 Not Locked N/A Unknown 0 Ksym/sec 0 Hz 0.0 dBmV

[EG]

The signal stats are o/k but the error log entries indicate that something is going on. Perhaps there is noise ingress into the line(s) 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 to see whether or not everything is in the green zone, see your node / cable plant and modem health, and also see a history plot for the modem. You should get a reply here in your topic. Good luck !

[ComcastMichael]

Greetings, Justus30! I appreciate you taking the time to reach out to us here on the forums. I hope you are having an amazing day! I apologize to hear of the issue you are having with your internet services. I certainly understand needing to have a reliable connection, especially during these times! I would like to have a closer look at the signal to see what could be going. Can you please send me a PM with your first and last name so I may further assist you?

To send a private message, please click my name "ComcastMichael" then select "Send a Message" on the right side.

[Justus30]

Sure thing. PM sent.