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cm1000 and xfinity issues or just Docsis 3.1 issue?
Hello all. I upgraded to the Gigabit plan with Xfinity. I use my own Modem (Arris Surfboard 3.0). After realizing I needed a Docsis 3.1 I bought the Motorola MB8600 or whatever but it was 3.1. Comcast...
I am having the same set of issues with Comcast in Seattle area. Anyone know what I can do to debug why the CM1000 is so spotty? Every few days I lose all connectivity and have to reboot the modem. Downloaded latest patches. With previous modem the thing would work for months no issues. My wife is saying I paid out the nose for CM1000 and the thing is much worse than the 30$ Motorola we used in the past. Can't really argue with her.
To debug I wrote a program to periodically connect ever 15 seconds to a remote site and verify connectivity. Sure enough about every 1-2 days I lose all connectivity and it does not recover. Have to cold boot modem. The logging on the modem looks pretty shoddy, how can I debug this thing?
Please reply with some specific things I can do to debug the CM1000. The logs are pretty weak.
Mine is only dropping about once every week or two, but I still think that's too often. Otherwise it's fast and I like it. Now that I figured out how to to disable the house alarm from waking me up in the middle of the night when it drops signal I am slightly less annoyed. It is stil a pain to discover as I am trying to leave for work I have to stop and go upstairs and make time to reboot it before I can set the alarm and leave for work, but still better than being awaked at 3 am by the alarm signaling it lost connectivity.
Personally, I think it's related to Comcast and all of the changes they have been making to the streaming portal since they are being sued by the people that bought Tivo for patent infringment. My modem worked fine and I had no trouble until after Thanksgiving when comcast disabled features in their streaming portal causing customers like me to call them four times a week about features they broke by accident in the process of hastily trying to comply with the court order to remove specific features. As they then tried to do damage control, and restore the ones they broke by accident, everytime their programmers made a change, they had to push those updates to each user and I think while thye were doing all that my problem was way worse. It seems to have gotten significantly better for me in the past month now that they have restored most o fthe collateral damage
Are you able to post the power levels of your connection?
DarrenM
Frequency start Value This field below allows you to modify the frequency the cable modem start with its scan during initialization and registration. Enter the new start frequency and restart the cable modem for it to take effect. Starting Frequency <tabindex=-1>Startup Procedure
Procedure Status Comment Acquire Downstream Channel 609000000 Hz Locked Connectivity State OK Operational Boot State OK Operational Configuration File OK ------------ Security Enable BPI+ <tabindex=-1>Downstream Bonded Channels
Channel Lock Status Modulation Channel ID Frequency Power SNR Correctables Uncorrectables 1 Locked QAM256 21 609000000 Hz 5.9 dBmV 40.1 dB 0 0 2 Locked QAM256 1 489000000 Hz 7.5 dBmV 41.1 dB 0 0 3 Locked QAM256 2 495000000 Hz 7.4 dBmV 41.0 dB 0 0 4 Locked QAM256 3 501000000 Hz 7.3 dBmV 40.9 dB 0 0 5 Locked QAM256 4 507000000 Hz 7.5 dBmV 37.8 dB 0 0 6 Locked QAM256 5 513000000 Hz 7.3 dBmV 41.0 dB 0 0 7 Locked QAM256 6 519000000 Hz 7.3 dBmV 40.9 dB 0 0 8 Locked QAM256 7 525000000 Hz 7.3 dBmV 40.8 dB 0 0 9 Locked QAM256 8 531000000 Hz 7.2 dBmV 40.8 dB 0 0 10 Locked QAM256 9 537000000 Hz 7.2 dBmV 40.7 dB 0 0 11 Locked QAM256 10 543000000 Hz 7.1 dBmV 40.6 dB 0 0 12 Locked QAM256 11 549000000 Hz 6.9 dBmV 40.4 dB 0 0 13 Locked QAM256 12 555000000 Hz 7.1 dBmV 40.6 dB 0 0 14 Locked QAM256 13 561000000 Hz 7.0 dBmV 40.2 dB 0 0 15 Locked QAM256 14 567000000 Hz 6.8 dBmV 40.3 dB 0 0 16 Locked QAM256 15 573000000 Hz 6.9 dBmV 40.3 dB 0 0 17 Locked QAM256 16 579000000 Hz 6.5 dBmV 40.8 dB 0 0 18 Locked QAM256 17 585000000 Hz 6.2 dBmV 40.8 dB 0 0 19 Locked QAM256 18 591000000 Hz 6.0 dBmV 40.3 dB 0 0 20 Locked QAM256 19 597000000 Hz 5.9 dBmV 40.3 dB 0 0 21 Locked QAM256 20 603000000 Hz 5.9 dBmV 40.3 dB 0 0 22 Locked QAM256 22 615000000 Hz 5.6 dBmV 39.9 dB 0 0 23 Locked QAM256 23 621000000 Hz 5.5 dBmV 39.9 dB 0 0 24 Locked QAM256 24 627000000 Hz 5.1 dBmV 39.4 dB 0 0 <tabindex=-1>Upstream Bonded Channels
Channel Lock Status US Channel Type Channel ID Symbol Rate Frequency Power 1 Locked ATDMA 1 5120 Ksym/sec 36100000 Hz 43.3 dBmV 2 Locked ATDMA 2 5120 Ksym/sec 29600000 Hz 43.5 dBmV 3 Locked ATDMA 3 5120 Ksym/sec 23000000 Hz 43.5 dBmV 4 Locked ATDMA 4 5120 Ksym/sec 16500000 Hz 43.5 dBmV 5 Not Locked Unknown 0 0 Ksym/sec 0 Hz 0.0 dBmV 6 Not Locked Unknown 0 0 Ksym/sec 0 Hz 0.0 dBmV 7 Not Locked Unknown 0 0 Ksym/sec 0 Hz 0.0 dBmV 8 Not Locked Unknown 0 0 Ksym/sec 0 Hz 0.0 dBmV Current System Time: Tue Apr 03 20:06:58 2018
Note here are my stats, look pretty good:
Cable Connection
Apply Cancel
Frequency start Value
This field below allows you to modify the frequency the cable modem start with its scan during initialization and registration. Enter the new start frequency and restart the cable modem for it to take effect.
Starting Frequency
639000000
Startup Procedure
Procedure Status Comment
Acquire Downstream Channel 639000000 Hz Locked
Connectivity State OK Operational
Boot State OK Operational
Security Enable BPI+
IP Provisioning Mode Honor MDD IPv6 only
Downstream Bonded Channels
Channel Lock Status Modulation Channel ID Frequency Power SNR / MER Unerrored Codewords Correctable Codewords Uncorrectable Codewords
1 Locked QAM256 25 639000000 Hz -1.0 dBmV 38.0 dB 224514965 97 0
2 Locked QAM256 1 483000000 Hz -1.0 dBmV 38.8 dB 221670518 6 0
3 Locked QAM256 2 489000000 Hz -0.7 dBmV 38.8 dB 221684214 1 0
4 Locked QAM256 3 495000000 Hz 0.0 dBmV 38.8 dB 221697351 2 0
5 Locked QAM256 4 507000000 Hz -1.7 dBmV 38.5 dB 221709990 2 0
6 Locked QAM256 5 513000000 Hz -3.3 dBmV 38.4 dB 221722831 3 0
7 Locked QAM256 6 519000000 Hz -3.3 dBmV 38.4 dB 221735725 8 0
8 Locked QAM256 7 525000000 Hz -2.2 dBmV 38.5 dB 221749433 5 0
9 Locked QAM256 8 531000000 Hz -1.8 dBmV 38.5 dB 221762336 10 0
10 Locked QAM256 9 543000000 Hz -2.0 dBmV 38.4 dB 221775443 8 0
11 Locked QAM256 10 549000000 Hz -2.9 dBmV 38.2 dB 221788520 8 0
12 Locked QAM256 11 555000000 Hz -3.0 dBmV 38.1 dB 221801376 18 0
13 Locked QAM256 12 561000000 Hz -2.5 dBmV 38.2 dB 221822634 20 0
14 Locked QAM256 13 567000000 Hz -2.2 dBmV 38.2 dB 221836130 17 0
15 Locked QAM256 14 573000000 Hz -1.9 dBmV 38.3 dB 221848501 25 0
16 Locked QAM256 15 579000000 Hz -2.1 dBmV 38.2 dB 221862091 28 0
17 Locked QAM256 16 585000000 Hz -2.0 dBmV 38.2 dB 221875431 27 0
18 Locked QAM256 17 591000000 Hz -1.9 dBmV 38.1 dB 221888649 24 0
19 Locked QAM256 18 597000000 Hz -1.5 dBmV 38.0 dB 221901593 44 0
20 Locked QAM256 19 603000000 Hz -1.2 dBmV 38.1 dB 221914425 37 0
21 Locked QAM256 20 609000000 Hz -1.1 dBmV 38.1 dB 221927939 54 0
22 Locked QAM256 21 615000000 Hz -1.1 dBmV 38.0 dB 221941485 57 0
23 Locked QAM256 22 621000000 Hz -1.3 dBmV 38.2 dB 221954893 46 0
24 Locked QAM256 23 627000000 Hz -1.5 dBmV 38.0 dB 221967464 80 0
25 Locked QAM256 24 633000000 Hz -1.2 dBmV 37.8 dB 221980886 71 0
26 Locked QAM256 26 645000000 Hz -1.0 dBmV 37.7 dB 221993619 79 0
27 Locked QAM256 27 651000000 Hz -1.2 dBmV 37.7 dB 222007106 111 0
28 Locked QAM256 28 657000000 Hz -1.5 dBmV 37.8 dB 222020222 81 0
29 Locked QAM256 29 663000000 Hz -1.4 dBmV 37.6 dB 222031542 87 0
30 Locked QAM256 30 669000000 Hz -1.2 dBmV 37.7 dB 222039345 75 0
31 Locked QAM256 31 675000000 Hz -1.3 dBmV 37.3 dB 222046242 86 0
32 Not Locked Unknown 0 0 Hz 0.0 dBmV 0.0 dB 0 0 0Upstream Bonded Channels
Channel Lock Status Modulation Channel ID Frequency Power
1 Locked ATDMA 1 30100000 Hz 63.3 dBmV
2 Not Locked Unknown 0 0 Hz 0.0 dBmV
3 Not Locked Unknown 0 0 Hz 0.0 dBmV
4 Not Locked Unknown 0 0 Hz 0.0 dBmV
5 Not Locked Unknown 0 0 Hz 0.0 dBmV
6 Not Locked Unknown 0 0 Hz 0.0 dBmV
7 Not Locked Unknown 0 0 Hz 0.0 dBmV
8 Not Locked Unknown 0 0 Hz 0.0 dBmV
Downstream OFDM Channels
Channel Lock Status Modulation / Profile ID Channel ID Frequency Power SNR / MER Active Subcarrier Number Range Unerrored Codewords Correctable Codewords Uncorrectable Codewords
1 Locked 0 159 745000000 Hz -0.8 dBmV 36.8 dB 1126 ~ 2969 188572963 0 0
2 Not Locked 0 0 0 Hz -4.3 dBmV 0.0 dB 0 ~ 4095 0 0 0
Upstream OFDMA Channels
Channel Lock Status Modulation / Profile ID Channel ID Frequency Power
1 Not Locked Unknown 0 0 Hz 0 dBmV
2 Not Locked Unknown 0 0 Hz 0 dBmV
Current System Time: Tue Apr 03 18:44:45 2018Help Center Show/Hide Help Center
All the levels look fine. Do you get any T3 or T4 timeouts in the logs?
DarrenM
Yes, lots of T3 timeouts.
Bought brand new Motorola MB8600, same spotty connectivity issues. Same T3 timeouts in log. Working to get Comcast out to my house to investigate. Comcast tech claimed to have "boosted" the signal of my modem via some mystical remote software patch of my modem. Still same problem.
Just a follow up. Comcast came out and replaced my outdoor splitter and signal now is great and modem rock solid. So root cause was poor signal due to faulty old splitter.
