U

Visitor

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2 Messages

Sat, Jul 31, 2021 7:02 AM

Identical outages three days in a row

Hi,

We turned our connection up at the end of April. After a honeymoon period where everything worked great, we started to experience intermittent outages. For the most part they're usually pretty short, but we have had a tech out once after one of the longer ones. They couldn't find any obvious issues, but did replace a connector on our tap at the pole just to be thorough, though that didn't seem to have any effect. My computer is connected via ethernet to a switch which connects to my router and then into my Arris SB8200 modem. There is no wifi involved and my router is working 100% fine. It appears to be that the modem is losing sync during these outages.

The connection had been solid for the past week and a half or so with zero issues, but then we started having intermittent outages again. I wouldn't get too excited about it, except that the connection has gone down at almost exactly the same time, in exactly the same way, three days in a row:

07/28/2021 20:40
07/29/2021 20:46
07/30/2021 21:14

The software that Comcast is pushing out to SB8200s appears to have a pretty egregious and unfortunate bug where often when you load the event log on the modem web interface it causes the web server in the modem to crash and become unresponsive until you restart the modem. For that reason I wasn't able to get any information from the logs the first two days, but was able to grab the information from todays outage. The other unfortunate bug is that either the SB8200 or the CMTS doesn't seem to know/care about daylight saving time, so the time in the logs is off by an hour. MAC addresses have been sanitized to protect the innocent:

Date Time       Event ID        Event Level     Description
07/30/2021 20:17        82000200        3       "No Ranging Response received - T3 time-out;CM-MAC=ec:a9:40:xx:xx:xx;CMTS-MAC=00:01:5c:xx:xx:xx;CM-QOS=1.1;CM-VER=3.1;"
07/30/2021 20:16        74010100        6       "CM-STATUS message sent. Event Type Code: 7; Chan ID: 1 2 4; DSID: N/A; MAC Addr: N/A; OFDM/OFDMA Profile ID: N/A.;CM-MAC=ec:a9:40:xx:xx:xx;CMTS-MAC=00:01:5c:xx:xx:xx;CM-QOS=1.1;CM-VER=3.1;"
07/30/2021 20:16        82000200        3       "No Ranging Response received - T3 time-out;CM-MAC=ec:a9:40:xx:xx:xx;CMTS-MAC=00:01:5c:xx:xx:xx;CM-QOS=1.1;CM-VER=3.1;"
07/30/2021 20:16        74010100        6       "CM-STATUS message sent. Event Type Code: 7; Chan ID: 1 2 4; DSID: N/A; MAC Addr: N/A; OFDM/OFDMA Profile ID: N/A.;CM-MAC=ec:a9:40:xx:xx:xx;CMTS-MAC=00:01:5c:xx:xx:xx;CM-QOS=1.1;CM-VER=3.1;"
07/30/2021 20:15        82000200        3       "No Ranging Response received - T3 time-out;CM-MAC=ec:a9:40:xx:xx:xx;CMTS-MAC=00:01:5c:xx:xx:xx;CM-QOS=1.1;CM-VER=3.1;"
07/30/2021 20:15        74010100        6       "CM-STATUS message sent. Event Type Code: 7; Chan ID: 1 2 4; DSID: N/A; MAC Addr: N/A; OFDM/OFDMA Profile ID: N/A.;CM-MAC=ec:a9:40:xx:xx:xx;CMTS-MAC=00:01:5c:xx:xx:xx;CM-QOS=1.1;CM-VER=3.1;"
07/30/2021 20:15        82000200        3       "No Ranging Response received - T3 time-out;CM-MAC=ec:a9:40:xx:xx:xx;CMTS-MAC=00:01:5c:xx:xx:xx;CM-QOS=1.1;CM-VER=3.1;"
07/30/2021 20:14        74010100        6       "CM-STATUS message sent. Event Type Code: 7; Chan ID: 1 2 4; DSID: N/A; MAC Addr: N/A; OFDM/OFDMA Profile ID: N/A.;CM-MAC=ec:a9:40:xx:xx:xx;CMTS-MAC=00:01:5c:xx:xx:xx;CM-QOS=1.1;CM-VER=3.1;"
07/30/2021 20:14        82000500        3       "Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=ec:a9:40:xx:xx:xx;CMTS-MAC=00:01:5c:xx:xx:xx;CM-QOS=1.1;CM-VER=3.1;"
07/30/2021 20:14        82000200        3       "No Ranging Response received - T3 time-out;CM-MAC=ec:a9:40:xx:xx:xx;CMTS-MAC=00:01:5c:xx:xx:xx;CM-QOS=1.1;CM-VER=3.1;"
07/30/2021 20:14        82000500        3       "Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=ec:a9:40:xx:xx:xx;CMTS-MAC=00:01:5c:xx:xx:xx;CM-QOS=1.1;CM-VER=3.1;"
07/30/2021 20:14        82000200        3       "No Ranging Response received - T3 time-out;CM-MAC=ec:a9:40:xx:xx:xx;CMTS-MAC=00:01:5c:xx:xx:xx;CM-QOS=1.1;CM-VER=3.1;"
07/30/2021 20:14        82000500        3       "Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=ec:a9:40:xx:xx:xx;CMTS-MAC=00:01:5c:xx:xx:xx;CM-QOS=1.1;CM-VER=3.1;"
07/30/2021 20:14        82000200        3       "No Ranging Response received - T3 time-out;CM-MAC=ec:a9:40:xx:xx:xx;CMTS-MAC=00:01:5c:xx:xx:xx;CM-QOS=1.1;CM-VER=3.1;"
07/30/2021 20:14        82000500        3       "Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=ec:a9:40:xx:xx:xx;CMTS-MAC=00:01:5c:xx:xx:xx;CM-QOS=1.1;CM-VER=3.1;"
07/30/2021 20:14        82000200        3       "No Ranging Response received - T3 time-out;CM-MAC=ec:a9:40:xx:xx:xx;CMTS-MAC=00:01:5c:xx:xx:xx;CM-QOS=1.1;CM-VER=3.1;"
07/30/2021 20:14        74010100        6       "CM-STATUS message sent. Event Type Code: 7; Chan ID: 1 2 4; DSID: N/A; MAC Addr: N/A; OFDM/OFDMA Profile ID: N/A.;CM-MAC=ec:a9:40:xx:xx:xx;CMTS-MAC=00:01:5c:xx:xx:xx;CM-QOS=1.1;CM-VER=3.1;"
07/30/2021 20:14        82000200        3       "No Ranging Response received - T3 time-out;CM-MAC=ec:a9:40:xx:xx:xx;CMTS-MAC=00:01:5c:xx:xx:xx;CM-QOS=1.1;CM-VER=3.1;"
07/30/2021 20:14        82000800        3       "16 consecutive T3 timeouts while trying to range on upstream channel 3;CM-MAC=ec:a9:40:xx:xx:xx;CMTS-MAC=00:01:5c:xx:xx:xx;CM-QOS=1.1;CM-VER=3.1;"
07/30/2021 20:14        82000600        3       "Unicast Maintenance Ranging attempted - No response - Retries exhausted;CM-MAC=ec:a9:40:xx:xx:xx;CMTS-MAC=00:01:5c:xx:xx:xx;CM-QOS=1.1;CM-VER=3.1;"
07/30/2021 20:14        82000500        3       "Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=ec:a9:40:xx:xx:xx;CMTS-MAC=00:01:5c:xx:xx:xx;CM-QOS=1.1;CM-VER=3.1;"
07/30/2021 20:14        82000200        3       "No Ranging Response received - T3 time-out;CM-MAC=ec:a9:40:xx:xx:xx;CMTS-MAC=00:01:5c:xx:xx:xx;CM-QOS=1.1;CM-VER=3.1;"
07/30/2021 20:14        82000800        3       "16 consecutive T3 timeouts while trying to range on upstream channel 2;CM-MAC=ec:a9:40:xx:xx:xx;CMTS-MAC=00:01:5c:xx:xx:xx;CM-QOS=1.1;CM-VER=3.1;"
07/30/2021 20:14        82000600        3       "Unicast Maintenance Ranging attempted - No response - Retries exhausted;CM-MAC=ec:a9:40:xx:xx:xx;CMTS-MAC=00:01:5c:xx:xx:xx;CM-QOS=1.1;CM-VER=3.1;"
07/30/2021 20:14        82000500        3       "Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=ec:a9:40:xx:xx:xx;CMTS-MAC=00:01:5c:xx:xx:xx;CM-QOS=1.1;CM-VER=3.1;"
07/30/2021 20:14        82000200        3       "No Ranging Response received - T3 time-out;CM-MAC=ec:a9:40:xx:xx:xx;CMTS-MAC=00:01:5c:xx:xx:xx;CM-QOS=1.1;CM-VER=3.1;"
07/30/2021 20:14        82000800        3       "16 consecutive T3 timeouts while trying to range on upstream channel 1;CM-MAC=ec:a9:40:xx:xx:xx;CMTS-MAC=00:01:5c:xx:xx:xx;CM-QOS=1.1;CM-VER=3.1;"
07/30/2021 20:14        82000600        3       "Unicast Maintenance Ranging attempted - No response - Retries exhausted;CM-MAC=ec:a9:40:xx:xx:xx;CMTS-MAC=00:01:5c:xx:xx:xx;CM-QOS=1.1;CM-VER=3.1;"
07/30/2021 20:14        82000500        3       "Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=ec:a9:40:xx:xx:xx;CMTS-MAC=00:01:5c:xx:xx:xx;CM-QOS=1.1;CM-VER=3.1;"
07/30/2021 20:08        74010100        6       "CM-STATUS message sent. Event Type Code: 24; Chan ID: 48; DSID: N/A; MAC Addr: N/A; OFDM/OFDMA Profile ID: 1 2 3.;CM-MAC=ec:a9:40:xx:xx:xx;CMTS-MAC=00:01:5c:xx:xx:xx;CM-QOS=1.1;CM-VER=3.1;"

I can't imagine any sort of wiring issue that would cause problems like clockwork three days in a row, so I don't know how much use rolling a tech out would be. Though I know that my signal levels aren't perfect, the connection is 100% solid with zero packet loss in the times between the intermittent outages. Is there anything that support can look at to see if this is part of a larger issue in my area/node?

Responses

EG

Expert

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89K Messages

2 m ago

An FYI. Modems do not do daylight savings time. It doesn't have any bearing on performance. Only the timestamps of the error log entries are affected.

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

Visitor

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2 Messages

2 m ago

@EG Yeah, I wasn't implying the time zone thing had anything to do with the connection quality, it's just an annoyance when troubleshooting. If they're going to set a time zone but ignore DST, they should just use UTC instead. But I guess that's a complaint for Arris not Comcast.

As I mentioned, the signal levels aren't great, but these are the current levels and the connection works perfectly right now and does so most of the time. Zero packet loss at these signal levels currently. And again, I'm not aware of any kind of wiring issue that can repeat itself three days in a row almost like clockwork.  

Downstream Bonded Channels
Channel ID Lock Status Modulation Frequency Power SNR/MER Corrected Uncorrectables
24 Locked QAM256 429000000 Hz -10.1 dBmV 39.6 dB 352381 61846
12 Locked QAM256 357000000 Hz -9.6 dBmV 39.7 dB 597399 149792
13 Locked QAM256 363000000 Hz -10.5 dBmV 39.2 dB 669976 173995
14 Locked QAM256 369000000 Hz -11.0 dBmV 38.8 dB 685387 171196
15 Locked QAM256 375000000 Hz -10.9 dBmV 39.0 dB 668251 158108
16 Locked QAM256 381000000 Hz -10.8 dBmV 39.2 dB 664580 143479
17 Locked QAM256 387000000 Hz -10.4 dBmV 39.4 dB 683054 151092
18 Locked QAM256 393000000 Hz -10.9 dBmV 39.0 dB 563220 114038
19 Locked QAM256 399000000 Hz -9.9 dBmV 39.5 dB 452433 92440
20 Locked QAM256 405000000 Hz -10.1 dBmV 39.5 dB 377117 75741
21 Locked QAM256 411000000 Hz -9.9 dBmV 39.5 dB 307358 57056
22 Locked QAM256 417000000 Hz -9.3 dBmV 39.9 dB 323544 64112
23 Locked QAM256 423000000 Hz -10.0 dBmV 39.7 dB 371981 70587
25 Locked QAM256 435000000 Hz -10.3 dBmV 39.6 dB 392735 73403
26 Locked QAM256 441000000 Hz -10.8 dBmV 39.5 dB 372608 66676
28 Locked QAM256 453000000 Hz -10.8 dBmV 39.5 dB 380416 68543
29 Locked QAM256 459000000 Hz -10.9 dBmV 39.4 dB 351040 63457
30 Locked QAM256 465000000 Hz -10.2 dBmV 39.7 dB 322305 53665
31 Locked QAM256 471000000 Hz -10.5 dBmV 39.7 dB 275594 45122
32 Locked QAM256 477000000 Hz -10.1 dBmV 39.8 dB 224140 33653
33 Locked QAM256 483000000 Hz -10.4 dBmV 39.6 dB 235727 36110
34 Locked QAM256 489000000 Hz -10.6 dBmV 39.5 dB 231819 35461
35 Locked QAM256 495000000 Hz -11.1 dBmV 39.3 dB 264247 41691
36 Locked QAM256 507000000 Hz -12.4 dBmV 38.8 dB 297525 50771
37 Locked QAM256 513000000 Hz -12.8 dBmV 38.5 dB 299377 52022
38 Locked QAM256 519000000 Hz -12.5 dBmV 39.0 dB 271124 43983
39 Locked QAM256 525000000 Hz -12.7 dBmV 38.7 dB 284047 47007
40 Locked QAM256 531000000 Hz -12.6 dBmV 38.9 dB 263523 43062
41 Locked QAM256 537000000 Hz -12.1 dBmV 39.0 dB 242565 37542
42 Locked QAM256 543000000 Hz -12.0 dBmV 39.1 dB 212654 29589
43 Locked QAM256 549000000 Hz -12.3 dBmV 38.9 dB 199581 27939
48 Locked Other 561000000 Hz -13.2 dBmV 36.2 dB 1032809752 7237423


Upstream Bonded Channels
Channel Channel ID Lock Status US Channel Type Frequency Width Power
1 1 Locked SC-QAM Upstream 16400000 Hz 6400000 Hz 59.0 dBmV
2 2 Locked SC-QAM Upstream 22800000 Hz 6400000 Hz 59.0 dBmV
3 3 Locked SC-QAM Upstream 29200000 Hz 6400000 Hz 59.0 dBmV
4 4 Locked SC-QAM Upstream 35600000 Hz 6400000 Hz 59.0 dBmV
This comment was created from this reply
EG

Expert

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89K Messages

@user_48baac

Your signals are terrible / out of spec !! Since you already had a tech visit, you should get them involved again until it is fixed properly.

Bear in mind that if the premises facing techs can not find or fix a problem at your home, it is they who are responsible for escalating it to their line / network / maintenance dept. techs. The problem may lie beyond your home in the local neighborhood infrastructure somewhere but it is their S.O.P. to start at the home.


Good luck !

 

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