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Consecutive T3 timeouts occuring on upstream channel 1 and 3

surajkattige056
Regular Visitor

Consecutive T3 timeouts occuring on upstream channel 1 and 3

Hello,

 

I have been experiencing internet issues for over a month now and I couldn't it successfully. I recently checked my logs and found the following event logs:

 

2020-5-18, 17:40:06 Critical (3) Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=14:59:c0:07:69:30;CMTS-MAC=00:01:5c:63:2e:8f;CM-QOS=1.1;CM-VER=3.0;
2020-5-18, 17:40:05 Critical (3) 16 consecutive T3 timeouts while trying to range on upstream channel 3;CM-MAC=14:59:c0:07:69:30;CMTS-MAC=00:01:5c:63:2e:8f;CM-QOS=1.1;CM-VER=3.0;
2020-5-18, 17:40:05 Critical (3) Unicast Maintenance Ranging attempted - No response - Retries exhausted;CM-MAC=14:59:c0:07:69:30;CMTS-MAC=00:01:5c:63:2e:8f;CM-QOS=1.1;CM-VER=3.0;
2020-5-18, 17:40:03 Critical (3) Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=14:59:c0:07:69:30;CMTS-MAC=00:01:5c:63:2e:8f;CM-QOS=1.1;CM-VER=3.0;
2020-5-18, 17:40:03 Critical (3) 16 consecutive T3 timeouts while trying to range on upstream channel 1;CM-MAC=14:59:c0:07:69:30;CMTS-MAC=00:01:5c:63:2e:8f;CM-QOS=1.1;CM-VER=3.0;
2020-5-18, 17:40:03 Critical (3) Unicast Maintenance Ranging attempted - No response - Retries exhausted;CM-MAC=14:59:c0:07:69:30;CMTS-MAC=00:01:5c:63:2e:8f;CM-QOS=1.1;CM-VER=3.0;
2020-5-18, 17:39:43 Critical (3) Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=14:59:c0:07:69:30;CMTS-MAC=00:01:5c:63:2e:8f;CM-QOS=1.1;CM-VER=3.0;
2020-5-18, 17:39:42 Critical (3) 16 consecutive T3 timeouts while trying to range on upstream channel 3;CM-MAC=14:59:c0:07:69:30;CMTS-MAC=00:01:5c:63:2e:8f;CM-QOS=1.1;CM-VER=3.0;
2020-5-18, 17:39:42 Critical (3) Unicast Maintenance Ranging attempted - No response - Retries exhausted;CM-MAC=14:59:c0:07:69:30;CMTS-MAC=00:01:5c:63:2e:8f;CM-QOS=1.1;CM-VER=3.0;
2020-5-18, 17:39:41 Critical (3) Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=14:59:c0:07:69:30;CMTS-MAC=00:01:5c:63:2e:8f;CM-QOS=1.1;CM-VER=3.0;
2020-5-18, 17:39:41 Critical (3) 16 consecutive T3 timeouts while trying to range on upstream channel 1;CM-MAC=14:59:c0:07:69:30;CMTS-MAC=00:01:5c:63:2e:8f;CM-QOS=1.1;CM-VER=3.0;
2020-5-18, 17:39:41 Critical (3) Unicast Maintenance Ranging attempted - No response - Retries exhausted;CM-MAC=14:59:c0:07:69:30;CMTS-MAC=00:01:5c:63:2e:8f;CM-QOS=1.1;CM-VER=3.0;
2020-5-18, 17:39:22 Critical (3) Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=14:59:c0:07:69:30;CMTS-MAC=00:01:5c:63:2e:8f;CM-QOS=1.1;CM-VER=3.0;
2020-5-18, 17:39:20 Critical (3) 16 consecutive T3 timeouts while trying to range on upstream channel 3;CM-MAC=14:59:c0:07:69:30;CMTS-MAC=00:01:5c:63:2e:8f;CM-QOS=1.1;CM-VER=3.0;
2020-5-18, 17:39:20 Critical (3) Unicast Maintenance Ranging attempted - No response - Retries exhausted;CM-MAC=14:59:c0:07:69:30;CMTS-MAC=00:01:5c:63:2e:8f;CM-QOS=1.1;CM-VER=3.0;
2020-5-18, 17:39:19 Critical (3) Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=14:59:c0:07:69:30;CMTS-MAC=00:01:5c:63:2e:8f;CM-QOS=1.1;CM-VER=3.0;
2020-5-18, 17:39:19 Critical (3) 16 consecutive T3 timeouts while trying to range on upstream channel 1;CM-MAC=14:59:c0:07:69:30;CMTS-MAC=00:01:5c:63:2e:8f;CM-QOS=1.1;CM-VER=3.0;
2020-5-18, 17:39:19 Critical (3) Unicast Maintenance Ranging attempted - No response - Retries exhausted;CM-MAC=14:59:c0:07:69:30;CMTS-MAC=00:01:5c:63:2e:8f;CM-QOS=1.1;CM-VER=3.0;
2020-5-18, 17:38:59 Critical (3) Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=14:59:c0:07:69:30;CMTS-MAC=00:01:5c:63:2e:8f;CM-QOS=1.1;CM-VER=3.0;
2020-5-18, 17:38:58 Critical (3) 16 consecutive T3 timeouts while trying to range on upstream channel 3;CM-MAC=14:59:c0:07:69:30;CMTS-MAC=00:01:5c:63:2e:8f;CM-QOS=1.1;CM-VER=3.0;
2020-5-18, 17:38:58 Critical (3) Unicast Maintenance Ranging attempted - No response - Retries exhausted;CM-MAC=14:59:c0:07:69:30;CMTS-MAC=00:01:5c:63:2e:8f;CM-QOS=1.1;CM-VER=3.0;
2020-5-18, 17:38:56 Critical (3) Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=14:59:c0:07:69:30;CMTS-MAC=00:01:5c:63:2e:8f;CM-QOS=1.1;CM-VER=3.0;
2020-5-18, 17:38:56 Critical (3) 16 consecutive T3 timeouts while trying to range on upstream channel 1;CM-MAC=14:59:c0:07:69:30;CMTS-MAC=00:01:5c:63:2e:8f;CM-QOS=1.1;CM-VER=3.0;
2020-5-18, 17:38:56 Critical (3) Unicast Maintenance Ranging attempted - No response - Retries exhausted;CM-MAC=14:59:c0:07:69:30;CMTS-MAC=00:01:5c:63:2e:8f;CM-QOS=1.1;CM-VER=3.0;
2020-5-18, 17:38:37 Critical (3) Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=14:59:c0:07:69:30;CMTS-MAC=00:01:5c:63:2e:8f;CM-QOS=1.1;CM-VER=3.0;
2020-5-18, 17:38:35 Critical (3) 16 consecutive T3 timeouts while trying to range on upstream channel 3;CM-MAC=14:59:c0:07:69:30;CMTS-MAC=00:01:5c:63:2e:8f;CM-QOS=1.1;CM-VER=3.0;
2020-5-18, 17:38:35 Critical (3) Unicast Maintenance Ranging attempted - No response - Retries exhausted;CM-MAC=14:59:c0:07:69:30;CMTS-MAC=00:01:5c:63:2e:8f;CM-QOS=1.1;CM-VER=3.0;
2020-5-18, 17:38:35 Critical (3) Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=14:59:c0:07:69:30;CMTS-MAC=00:01:5c:63:2e:8f;CM-QOS=1.1;CM-VER=3.0;
2020-5-18, 17:38:35 Critical (3) 16 consecutive T3 timeouts while trying to range on upstream channel 1;CM-MAC=14:59:c0:07:69:30;CMTS-MAC=00:01:5c:63:2e:8f;CM-QOS=1.1;CM-VER=3.0;
2020-5-18, 17:38:35 Critical (3) Unicast Maintenance Ranging attempted - No response - Retries exhausted;CM-MAC=14:59:c0:07:69:30;CMTS-MAC=00:01:5c:63:2e:8f;CM-QOS=1.1;CM-VER=3.0;
2020-5-18, 17:38:14 Critical (3) Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=14:59:c0:07:69:30;CMTS-MAC=00:01:5c:63:2e:8f;CM-QOS=1.1;CM-VER=3.0;
2020-5-18, 17:38:13 Critical (3) 16 consecutive T3 timeouts while trying to range on upstream channel 3;CM-MAC=14:59:c0:07:69:30;CMTS-MAC=00:01:5c:63:2e:8f;CM-QOS=1.1;CM-VER=3.0;
2020-5-18, 17:38:13 Critical (3) Unicast Maintenance Ranging attempted - No response - Retries exhausted;CM-MAC=14:59:c0:07:69:30;CMTS-MAC=00:01:5c:63:2e:8f;CM-QOS=1.1;CM-VER=3.0;
2020-5-18, 17:38:12 Critical (3) Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=14:59:c0:07:69:30;CMTS-MAC=00:01:5c:63:2e:8f;CM-QOS=1.1;CM-VER=3.0;
2020-5-18, 17:38:12 Critical (3) 16 consecutive T3 timeouts while trying to range on upstream channel 1;CM-MAC=14:59:c0:07:69:30;CMTS-MAC=00:01:5c:63:2e:8f;CM-QOS=1.1;CM-VER=3.0;
2020-5-18, 17:38:12 Critical (3) Unicast Maintenance Ranging attempted - No response - Retries exhausted;CM-MAC=14:59:c0:07:69:30;CMTS-MAC=00:01:5c:63:2e:8f;CM-QOS=1.1;CM-VER=3.0;
2020-5-18, 17:37:52 Critical (3) Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=14:59:c0:07:69:30;CMTS-MAC=00:01:5c:63:2e:8f;CM-QOS=1.1;CM-VER=3.0;
2020-5-18, 17:37:51 Critical (3) 16 consecutive T3 timeouts while trying to range on upstream channel 3;CM-MAC=14:59:c0:07:69:30;CMTS-MAC=00:01:5c:63:2e:8f;CM-QOS=1.1;CM-VER=3.0;
2020-5-18, 17:37:51 Critical (3) Unicast Maintenance Ranging attempted - No response - Retries exhausted;CM-MAC=14:59:c0:07:69:30;CMTS-MAC=00:01:5c:63:2e:8f;CM-QOS=1.1;CM-VER=3.0;
2020-5-18, 17:37:49 Critical (3)

Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=14:59:c0:07:69:30;CMTS-MAC=00:01:5c:63:2e:8f;CM-QOS=1.1;CM-VER=3.0;

 

 

Not sure if they are related, but I checked my logs and observed that I am getting a lot of these messages: (I edited the target address)

 

Description Count Last Occurrence Target Source
[DoS attack: Teardrop or derivative] from 132.0.179.0, port 0 2 Mon May 18 17:00:01 2020 xxx.xxx.xxx.xxx:0 132.0.179.0:0
[DoS attack: Ping Of Death] from 132.0.179.0, port 0 3 Mon May 18 16:59:51 2020 xxx.xxx.xxx.xxx:0 132.0.179.0:0
[DoS attack: Teardrop or derivative] from 132.0.179.0, port 0 1 Mon May 18 16:56:11 2020 xxx.xxx.xxx.xxx:0 132.0.179.0:0
[DoS attack: Ping Of Death] from 132.0.179.0, port 0 7 Mon May 18 16:55:29 2020 xxx.xxx.xxx.xxx:0 132.0.179.0:0
[DoS attack: Teardrop or derivative] from 132.0.179.0, port 0 1 Mon May 18 16:51:20 2020 xxx.xxx.xxx.xxx:0 132.0.179.0:0
[DoS attack: Ping Of Death] from 132.0.179.0, port 0 1 Mon May 18 16:51:20 2020 xxx.xxx.xxx.xxx:0 132.0.179.0:0
[DoS attack: Illegal Fragments] from 132.0.179.0, port 0 1 Mon May 18 16:51:20 2020 xxx.xxx.xxx.xxx:0 132.0.179.0:0

 

These are my downstream and upstream tables:

Downstream Bonded Channels
Channel Lock Status Modulation Channel ID Frequency Power SNR Correctables Uncorrectables
1 Locked QAM256 8 447000000 Hz 7.2 dBmV 39.1 dB 706 0
2 Locked QAM256 9 453000000 Hz 7.1 dBmV 38.8 dB 890 0
3 Locked QAM256 10 459000000 Hz 6.5 dBmV 38.2 dB 994 0
4 Locked QAM256 11 465000000 Hz 6.3 dBmV 38.1 dB 1146 0
5 Locked QAM256 12 471000000 Hz 6.5 dBmV 38.4 dB 1162 0
6 Locked QAM256 13 477000000 Hz 5.9 dBmV 38.3 dB 1164 0
7 Locked QAM256 14 483000000 Hz 5.4 dBmV 38.1 dB 1087 0
8 Locked QAM256 15 489000000 Hz 5.6 dBmV 38.5 dB 1272 0
9 Locked QAM256 16 495000000 Hz 5.9 dBmV 38.4 dB 1372 0
10 Locked QAM256 17 507000000 Hz 6.3 dBmV 37.7 dB 1558 0
11 Locked QAM256 18 513000000 Hz 6.1 dBmV 38.1 dB 1705 0
12 Locked QAM256 19 519000000 Hz 6.4 dBmV 38.2 dB 1736 0
13 Locked QAM256 20 525000000 Hz 6.9 dBmV 38.2 dB 1686 0
14 Locked QAM256 21 531000000 Hz 6.9 dBmV 38.4 dB 2202 0
15 Locked QAM256 22 537000000 Hz 6.8 dBmV 38.5 dB 2714 0
16 Locked QAM256 23 543000000 Hz 6.7 dBmV 38.6 dB 2867 0
 
Upstream Bonded Channels (Partial Service)
Channel Lock Status US Channel Type Channel ID Symbol Rate Frequency Power
1 Locked ATDMA 3 5120 Ksym/sec 30300000 Hz 45 dBmV
2 Not Locked Unknown 1 0 Ksym/sec 17300000 Hz 0.0 dBmV
3 Locked ATDMA 5 1280 Ksym/sec 41200000 Hz 43.3 dBmV
4 Not Locked Unknown 2 0 Ksym/sec 23700000 Hz 0.0 dBmV

 

I had called xfinity customer support a while ago and they couldn't find any problems. I am having a difficulty in streaming due to this issue.

 

Any chance anyone could help me out with this? Thanks in advance for the help.

CCAndrew
Diamond Problem Solver

Re: Consecutive T3 timeouts occuring on upstream channel 1 and 3

You probably have a high pass filter on your drop. Put there by maintenance if you have large amounts of ingress. 2 of your upstream channels aren’t registering and that’s the normal result.

I am a Retired Official Comcast Employee
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surajkattige056
Regular Visitor

Re: Consecutive T3 timeouts occuring on upstream channel 1 and 3

Thanks for the reply, I really appreciate it!

So what's the solution to this? And what can I do from my end?
CCAndrew
Diamond Problem Solver

Re: Consecutive T3 timeouts occuring on upstream channel 1 and 3

If that is the case, you’ll need a tech. Normally, there are notes on your account that it’s there, depending on the timing. Try another modem reboot to see if those 2 channels come back first.

I am a Retired Official Comcast Employee
We ask that you post publicly so people with similar questions may benefit from the conversation.
Was your question answered? Mark a post as the Best Answer!
surajkattige056
Regular Visitor

Re: Consecutive T3 timeouts occuring on upstream channel 1 and 3

Restarted my modem and the same upload channels give this problem. I actually started facing this issue after one of the routine comcast maintenances in my area. I will give comcast a call tomorrow and see if I can schedule a tech visit to check this out. Thanks for all your help! 🙂