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Frequent Internet Outages

Romdeau4
Frequent Visitor
‎12-23-2019 08:26 AM

Frequent Internet Outages

Hello,

 

I have been experiencing regular outages ranging from 2 or 3 minutes to 10-15 minutes at least once a day. I use my own modem/router and it's reporting upstream issues. It's been an ongoing issue for several weeks now and I've been reassured by live chat that it has been resolved several times. I just recently started monitoring the uptime:

Event	Date-Time	Reason	Duration
Up	2019-12-23 07:48:51	Successful Response	0 hrs, 15 mins
Down	2019-12-23 07:42:24	No Response	0 hrs, 6 mins
Up	2019-12-23 05:08:44	Successful Response	2 hrs, 33 mins
Down	2019-12-23 05:05:05	No Response	0 hrs, 3 mins
Up	2019-12-23 04:53:59	Successful Response	0 hrs, 11 mins
Down	2019-12-23 04:50:31	No Response	0 hrs, 3 mins
Up	2019-12-22 10:51:29	Successful Response	17 hrs, 59 mins
Down	2019-12-22 10:50:28	No Response	0 hrs, 1 mins
Up	2019-12-22 05:30:28	Successful Response	5 hrs, 20 mins
Down	2019-12-22 05:30:11	No Response	0 hrs, 0 mins
Up	2019-12-21 09:03:15	Successful Response	20 hrs, 26 mins
Down	2019-12-21 08:55:06	No Response	0 hrs, 8 mins
Up	2019-12-20 16:50:45	Successful Response	16 hrs, 4 mins
Down	2019-12-20 16:44:26	No Response	0 hrs, 6 mins
Up	2019-12-20 16:18:51	Successful Response	0 hrs, 25 mins
Down	2019-12-20 16:15:00	No Response	0 hrs, 3 mins
Up	2019-12-20 10:12:53	Successful Response	6 hrs, 2 mins
Down	2019-12-20 10:12:26	No Response	0 hrs, 0 mins
Up	2019-12-19 23:14:41	Successful Response	10 hrs, 57 mins
Down	2019-12-19 23:05:03	No Response	0 hrs, 9 mins
Up	2019-12-19 10:29:49	Successful Response	12 hrs, 35 mins
Down	2019-12-19 10:25:09	No Response	0 hrs, 4 mins
Up	2019-12-17 15:36:31	Successful Response	42 hrs, 48 mins
Down	2019-12-17 15:26:22	No Response	0 hrs, 10 mins
Up	2019-12-17 08:39:05	Successful Response	6 hrs, 47 mins
Started	2019-12-17 08:38:23	Started	0 hrs, 0 mins

My modem is reporting consistent T3 timeouts on the upstream channel during these outages:

Severity	Event
 Critical (3) 	 16 consecutive T3 timeouts while trying to range on upstream channel 2;CM-MAC=00:40:36:58:54:2e;CMTS-MAC=00:01:5c:7b:d0:62;CM-QOS=1.1;CM-VER=3.0; 
 Critical (3) 	 Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=00:40:36:58:54:2e;CMTS-MAC=00:01:5c:7b:d0:62;CM-QOS=1.1;CM-VER=3.0; 
 Critical (3) 	 Unicast Maintenance Ranging attempted - No response - Retries exhausted;CM-MAC=00:40:36:58:54:2e;CMTS-MAC=00:01:5c:7b:d0:62;CM-QOS=1.1;CM-VER=3.0; 
 Critical (3) 	 16 consecutive T3 timeouts while trying to range on upstream channel 3;CM-MAC=00:40:36:58:54:2e;CMTS-MAC=00:01:5c:7b:d0:62;CM-QOS=1.1;CM-VER=3.0; 
 Critical (3) 	 Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=00:40:36:58:54:2e;CMTS-MAC=00:01:5c:7b:d0:62;CM-QOS=1.1;CM-VER=3.0; 
 Critical (3) 	 Unicast Maintenance Ranging attempted - No response - Retries exhausted;CM-MAC=00:40:36:58:54:2e;CMTS-MAC=00:01:5c:7b:d0:62;CM-QOS=1.1;CM-VER=3.0; 
 Critical (3) 	 16 consecutive T3 timeouts while trying to range on upstream channel 1;CM-MAC=00:40:36:58:54:2e;CMTS-MAC=00:01:5c:7b:d0:62;CM-QOS=1.1;CM-VER=3.0; 
 Critical (3) 	 Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=00:40:36:58:54:2e;CMTS-MAC=00:01:5c:7b:d0:62;CM-QOS=1.1;CM-VER=3.0; 
 Critical (3) 	 Unicast Maintenance Ranging attempted - No response - Retries exhausted;CM-MAC=00:40:36:58:54:2e;CMTS-MAC=00:01:5c:7b:d0:62;CM-QOS=1.1;CM-VER=3.0; 
 Critical (3) 	 16 consecutive T3 timeouts while trying to range on upstream channel 2;CM-MAC=00:40:36:58:54:2e;CMTS-MAC=00:01:5c:7b:d0:62;CM-QOS=1.1;CM-VER=3.0; 
 Critical (3) 	 Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=00:40:36:58:54:2e;CMTS-MAC=00:01:5c:7b:d0:62;CM-QOS=1.1;CM-VER=3.0; 
 Critical (3) 	 Unicast Maintenance Ranging attempted - No response - Retries exhausted;CM-MAC=00:40:36:58:54:2e;CMTS-MAC=00:01:5c:7b:d0:62;CM-QOS=1.1;CM-VER=3.0; 
 Critical (3) 	 16 consecutive T3 timeouts while trying to range on upstream channel 3;CM-MAC=00:40:36:58:54:2e;CMTS-MAC=00:01:5c:7b:d0:62;CM-QOS=1.1;CM-VER=3.0; 
 Critical (3) 	 Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=00:40:36:58:54:2e;CMTS-MAC=00:01:5c:7b:d0:62;CM-QOS=1.1;CM-VER=3.0; 
 Critical (3) 	 Unicast Maintenance Ranging attempted - No response - Retries exhausted;CM-MAC=00:40:36:58:54:2e;CMTS-MAC=00:01:5c:7b:d0:62;CM-QOS=1.1;CM-VER=3.0; 
 Critical (3) 	 16 consecutive T3 timeouts while trying to range on upstream channel 1;CM-MAC=00:40:36:58:54:2e;CMTS-MAC=00:01:5c:7b:d0:62;CM-QOS=1.1;CM-VER=3.0; 
 Critical (3) 	 Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=00:40:36:58:54:2e;CMTS-MAC=00:01:5c:7b:d0:62;CM-QOS=1.1;CM-VER=3.0; 
 Critical (3) 	 Unicast Maintenance Ranging attempted - No response - Retries exhausted;CM-MAC=00:40:36:58:54:2e;CMTS-MAC=00:01:5c:7b:d0:62;CM-QOS=1.1;CM-VER=3.0; 
 Critical (3) 	 16 consecutive T3 timeouts while trying to range on upstream channel 2;CM-MAC=00:40:36:58:54:2e;CMTS-MAC=00:01:5c:7b:d0:62;CM-QOS=1.1;CM-VER=3.0; 
 Critical (3) 	 Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=00:40:36:58:54:2e;CMTS-MAC=00:01:5c:7b:d0:62;CM-QOS=1.1;CM-VER=3.0; 
 Critical (3) 	 Unicast Maintenance Ranging attempted - No response - Retries exhausted;CM-MAC=00:40:36:58:54:2e;CMTS-MAC=00:01:5c:7b:d0:62;CM-QOS=1.1;CM-VER=3.0; 
 Critical (3) 	 16 consecutive T3 timeouts while trying to range on upstream channel 3;CM-MAC=00:40:36:58:54:2e;CMTS-MAC=00:01:5c:7b:d0:62;CM-QOS=1.1;CM-VER=3.0; 
 Critical (3) 	 Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=00:40:36:58:54:2e;CMTS-MAC=00:01:5c:7b:d0:62;CM-QOS=1.1;CM-VER=3.0; 
 Critical (3) 	 Unicast Maintenance Ranging attempted - No response - Retries exhausted;CM-MAC=00:40:36:58:54:2e;CMTS-MAC=00:01:5c:7b:d0:62;CM-QOS=1.1;CM-VER=3.0; 
 Critical (3) 	 16 consecutive T3 timeouts while trying to range on upstream channel 1;CM-MAC=00:40:36:58:54:2e;CMTS-MAC=00:01:5c:7b:d0:62;CM-QOS=1.1;CM-VER=3.0; 
 Critical (3) 	 Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=00:40:36:58:54:2e;CMTS-MAC=00:01:5c:7b:d0:62;CM-QOS=1.1;CM-VER=3.0; 
 Critical (3) 	 Unicast Maintenance Ranging attempted - No response - Retries exhausted;CM-MAC=00:40:36:58:54:2e;CMTS-MAC=00:01:5c:7b:d0:62;CM-QOS=1.1;CM-VER=3.0; 
 Critical (3) 	 16 consecutive T3 timeouts while trying to range on upstream channel 2;CM-MAC=00:40:36:58:54:2e;CMTS-MAC=00:01:5c:7b:d0:62;CM-QOS=1.1;CM-VER=3.0; 
 Critical (3) 	 Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=00:40:36:58:54:2e;CMTS-MAC=00:01:5c:7b:d0:62;CM-QOS=1.1;CM-VER=3.0; 
 Critical (3) 	 Unicast Maintenance Ranging attempted - No response - Retries exhausted;CM-MAC=00:40:36:58:54:2e;CMTS-MAC=00:01:5c:7b:d0:62;CM-QOS=1.1;CM-VER=3.0; 
 Critical (3) 	 16 consecutive T3 timeouts while trying to range on upstream channel 3;CM-MAC=00:40:36:58:54:2e;CMTS-MAC=00:01:5c:7b:d0:62;CM-QOS=1.1;CM-VER=3.0; 
 Critical (3) 	 Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=00:40:36:58:54:2e;CMTS-MAC=00:01:5c:7b:d0:62;CM-QOS=1.1;CM-VER=3.0; 
 Critical (3) 	 16 consecutive T3 timeouts while trying to range on upstream channel 2;CM-MAC=00:40:36:58:54:2e;CMTS-MAC=00:01:5c:7b:d0:62;CM-QOS=1.1;CM-VER=3.0; 
 Critical (3) 	 Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=00:40:36:58:54:2e;CMTS-MAC=00:01:5c:7b:d0:62;CM-QOS=1.1;CM-VER=3.0; 
 Critical (3) 	 Unicast Maintenance Ranging attempted - No response - Retries exhausted;CM-MAC=00:40:36:58:54:2e;CMTS-MAC=00:01:5c:7b:d0:62;CM-QOS=1.1;CM-VER=3.0; 
 Critical (3) 	 16 consecutive T3 timeouts while trying to range on upstream channel 3;CM-MAC=00:40:36:58:54:2e;CMTS-MAC=00:01:5c:7b:d0:62;CM-QOS=1.1;CM-VER=3.0; 
 Critical (3) 	 Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=00:40:36:58:54:2e;CMTS-MAC=00:01:5c:7b:d0:62;CM-QOS=1.1;CM-VER=3.0; 
 Critical (3) 	 Unicast Maintenance Ranging attempted - No response - Retries exhausted;CM-MAC=00:40:36:58:54:2e;CMTS-MAC=00:01:5c:7b:d0:62;CM-QOS=1.1;CM-VER=3.0; 
 Critical (3) 	 16 consecutive T3 timeouts while trying to range on upstream channel 1;CM-MAC=00:40:36:58:54:2e;CMTS-MAC=00:01:5c:7b:d0:62;CM-QOS=1.1;CM-VER=3.0; 
 Critical (3) 	 Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=00:40:36:58:54:2e;CMTS-MAC=00:01:5c:7b:d0:62;CM-QOS=1.1;CM-VER=3.0; 
 Critical (3) 	 Unicast Maintenance Ranging attempted - No response - Retries exhausted;CM-MAC=00:40:36:58:54:2e;CMTS-MAC=00:01:5c:7b:d0:62;CM-QOS=1.1;CM-VER=3.0; 
 Critical (3) 	 16 consecutive T3 timeouts while trying to range on upstream channel 2;CM-MAC=00:40:36:58:54:2e;CMTS-MAC=00:01:5c:7b:d0:62;CM-QOS=1.1;CM-VER=3.0; 
 Critical (3) 	 Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=00:40:36:58:54:2e;CMTS-MAC=00:01:5c:7b:d0:62;CM-QOS=1.1;CM-VER=3.0; 
 Critical (3) 	 Unicast Maintenance Ranging attempted - No response - Retries exhausted;CM-MAC=00:40:36:58:54:2e;CMTS-MAC=00:01:5c:7b:d0:62;CM-QOS=1.1;CM-VER=3.0; 
 Critical (3) 	 16 consecutive T3 timeouts while trying to range on upstream channel 3;CM-MAC=00:40:36:58:54:2e;CMTS-MAC=00:01:5c:7b:d0:62;CM-QOS=1.1;CM-VER=3.0; 
 Critical (3) 	 Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=00:40:36:58:54:2e;CMTS-MAC=00:01:5c:7b:d0:62;CM-QOS=1.1;CM-VER=3.0; 
 Critical (3) 	 Unicast Maintenance Ranging attempted - No response - Retries exhausted;CM-MAC=00:40:36:58:54:2e;CMTS-MAC=00:01:5c:7b:d0:62;CM-QOS=1.1;CM-VER=3.0; 
 Critical (3) 	 16 consecutive T3 timeouts while trying to range on upstream channel 1;CM-MAC=00:40:36:58:54:2e;CMTS-MAC=00:01:5c:7b:d0:62;CM-QOS=1.1;CM-VER=3.0; 
 Critical (3) 	 Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=00:40:36:58:54:2e;CMTS-MAC=00:01:5c:7b:d0:62;CM-QOS=1.1;CM-VER=3.0; 
 Critical (3) 	 Unicast Maintenance Ranging attempted - No response - Retries exhausted;CM-MAC=00:40:36:58:54:2e;CMTS-MAC=00:01:5c:7b:d0:62;CM-QOS=1.1;CM-VER=3.0; 
 Critical (3) 	 16 consecutive T3 timeouts while trying to range on upstream channel 2;CM-MAC=00:40:36:58:54:2e;CMTS-MAC=00:01:5c:7b:d0:62;CM-QOS=1.1;CM-VER=3.0; 
 Critical (3) 	 Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=00:40:36:58:54:2e;CMTS-MAC=00:01:5c:7b:d0:62;CM-QOS=1.1;CM-VER=3.0; 
 Critical (3) 	 Unicast Maintenance Ranging attempted - No response - Retries exhausted;CM-MAC=00:40:36:58:54:2e;CMTS-MAC=00:01:5c:7b:d0:62;CM-QOS=1.1;CM-VER=3.0; 
 Critical (3) 	 16 consecutive T3 timeouts while trying to range on upstream channel 3;CM-MAC=00:40:36:58:54:2e;CMTS-MAC=00:01:5c:7b:d0:62;CM-QOS=1.1;CM-VER=3.0; 
 Critical (3) 	 Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=00:40:36:58:54:2e;CMTS-MAC=00:01:5c:7b:d0:62;CM-QOS=1.1;CM-VER=3.0; 
 Critical (3) 	 Unicast Maintenance Ranging attempted - No response - Retries exhausted;CM-MAC=00:40:36:58:54:2e;CMTS-MAC=00:01:5c:7b:d0:62;CM-QOS=1.1;CM-VER=3.0; 
 Critical (3) 	 16 consecutive T3 timeouts while trying to range on upstream channel 1;CM-MAC=00:40:36:58:54:2e;CMTS-MAC=00:01:5c:7b:d0:62;CM-QOS=1.1;CM-VER=3.0; 
 Critical (3) 	 Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=00:40:36:58:54:2e;CMTS-MAC=00:01:5c:7b:d0:62;CM-QOS=1.1;CM-VER=3.0; 
 Critical (3) 	 Unicast Maintenance Ranging attempted - No response - Retries exhausted;CM-MAC=00:40:36:58:54:2e;CMTS-MAC=00:01:5c:7b:d0:62;CM-QOS=1.1;CM-VER=3.0; 

Has anyone experienced similar issues? I telecommute for work and these regular interruptions are severly impacting meetings and other work.

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EG
Expert
‎12-23-2019 09:05 AM

Re: Frequent Internet Outages

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

What is the exact make and model number of the modem ?

Is this a WiFi connection ?



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Romdeau4
Frequent Visitor
‎12-23-2019 09:42 AM

Re: Frequent Internet Outages

The modem is a Motorola MG7540.

 

Downstream:

Channel 	Lock Status 	Modulation 	Channel ID 	Freq. (MHz) 	Pwr (dBmV) 	SNR (dB) 	Corrected 	Uncorrected
1	Locked	QAM256	34	453.0	4.1	39.5	0	0
2	Locked	QAM256	35	459.0	4.5	39.5	0	0
3	Locked	QAM256	36	465.0	4.5	39.6	0	0
4	Locked	QAM256	37	471.0	4.6	39.5	0	0
5	Locked	QAM256	1	477.0	4.6	39.3	0	0
6	Locked	QAM256	2	483.0	4.8	39.3	0	0
7	Locked	QAM256	3	489.0	5.0	39.4	0	0
8	Locked	QAM256	4	495.0	5.0	39.4	0	0
9	Locked	QAM256	5	507.0	4.4	37.6	0	0
10	Locked	QAM256	6	513.0	4.2	38.9	0	0
11	Locked	QAM256	7	519.0	4.4	39.1	0	0
12	Locked	QAM256	8	525.0	4.4	39.2	0	0
13	Locked	QAM256	9	531.0	4.0	39.0	0	0
14	Locked	QAM256	10	537.0	3.5	38.6	0	0
15	Locked	QAM256	11	543.0	3.3	38.6	0	0
16	Locked	QAM256	12	549.0	3.0	38.5	0	0
Total	 	 	 	 	 	 	0	0

Upstream:

Channel 	Lock Status 	Channel Type 	Channel ID 	Symb. Rate (Ksym/sec) 	Freq. (MHz) 	Pwr (dBmV)
1	Locked	ATDMA	5	5120	35.8	34.0
2	Locked	ATDMA	6	5120	29.4	33.9
3	Locked	ATDMA	7	5120	23.0	34.0
4	Locked	ATDMA	8	5120	16.6	34.0

I'm not logging the pwr and snr and my internet is fine at the moment. I'll try and grab them next time it goes out later today if needed.

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EG
Expert
‎12-23-2019 10:06 AM

Re: Frequent Internet Outages

These appear to be the typical looking downstream power levels and the SNR's;

 

Screenshot.png

 

but they seem to be in the incorrect columns. Same below for the upstream channels;

 

Screenshot2.png

and they are all in spec. Strange formatting there....

 



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Romdeau4
Frequent Visitor
‎12-23-2019 10:23 AM

Re: Frequent Internet Outages

I had just copy/pasted from my modem's admin panel. Here's a couple of screenshots: https://imgur.com/a/sJTgKmx

 

I'll try and get another screenshot later today of the values when the outages occurs.

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EG
Expert
‎12-23-2019 11:04 AM

Re: Frequent Internet Outages

As stated, all are good. The modem's RF error / event log entries are not so good. 



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Romdeau4
Frequent Visitor
‎12-28-2019 05:59 PM

Re: Frequent Internet Outages

Given the modem logs indicate upstream issues but there doesn’t appear to be interference, would this indicate issues with my modem or possibly issues originating from Xfinity that may require a technician to resolve?
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EG
Expert
‎12-28-2019 06:10 PM

Re: Frequent Internet Outages

Even though the signal stats looked o/k at that snapshot in time, the error log entries confirm 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 can check the CMTS (Cable Modem Termination System) for any real time degradation and / or error reports, see your node / cable plant and modem health, and see whether or not everything is in the green zone. They can also see a history plot for the modem and poll for those upstream receive signal stats.

You should get a reply here in your topic. Good luck !



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ComcastTambrey
Official Employee
‎12-29-2019 10:30 AM

Re: Frequent Internet Outages

Hello, Romdeau4!

I'm really glad you reached out to us about this. It definitely seems like there are some issues that we need to take a closer look at so we can get you back to a reliable connection for you to enjoy.  Please send me a private message with your first and last name, as well as your service address so I can assist. 

 

 To send a private message, click my name "ComcastTambrey", then click "send a message".


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Romdeau4
Frequent Visitor
‎12-30-2019 04:53 PM

Re: Frequent Internet Outages

For visibility and transparency,

 

ComcastTambrey was able to review my service's health reports and confirmed we experience a large volume of timeouts and upstream issues. It appears to be a physical issue and will require a technician to visit and troubleshoot in person.

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EG
Expert
‎12-30-2019 04:55 PM

Re: Frequent Internet Outages

Good luck with it ! Please post back with how things turn out.



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Romdeau4
Frequent Visitor
‎06-13-2020 10:10 AM

Poor Upload Speeds - T3 time-out

Hello,

 

I previously posted an issue here in regards to internet connectivity dropped for about 10-15 minute intervals a few times a day. It was recommended I have a technician schedule a visit and inspect my setup. The tech arrived, made some changes and confirmed any further issues would be a result of my modem rather than an issue Xfinity could resolve. After the tech left, my internet continued to drop intermittently and I chalked it up to a bad modem. I have recently purchased a new one (NETGEAR CM700), and confirmed stable internet, but now my speeds are horrible. I am subscribed to a 250/20 plan, but have not been able to receive speeds close to that at all. The following are the results of a recent speed test:

 

:::.. Internet Speed Test Result Details ..:::
Download Connection Speed:: 16814.76 kbps or 16.8 Mbps
Download Speed Test Size:: 13.2 MB or 13516 kB or 13840547.84 bytes
Download Binary File Transfer Speed:: 2102 kB/s or 2.1 MB/s
Upload Connection Speed:: 842 kbps or 0.8 Mbps
Upload Speed Test Size:: 1.2 MB or 1224 kB or 1253376 bytes
Upload Binary File Transfer Speed:: 105 kB/s
Timed:: Download: 6.585 seconds | Upload: 11.914 seconds
Tested At:: https://TestMy.net
Test Time:: 2020-06-13 09:02:28 Local Time
Client Location:: DeBary, FL US https://testmy.net/city/debary_fl
Target:: Miami, FL https://testmy.net/multithread
Validation:: https://testmy.net/db/RZG9RyyY6.hK9Qqk4FL
TiP Measurement Summary (Download):: Min 3.71 Mbps | Middle Avg 31.81 Mbps | Max 57.3 Mbps | 176% Variance
Client Stats:: https://testmy.net/compID/699353589223
User Agent:: Mozilla/5.0 (X11; Fedora; Linux x86_64; rv:77.0) Gecko/20100101 Firefox/77.0 [!]

 

Reviewing the modem's logs, I see similar errors that my previous modem encountered, including the T3 timeouts:

  Warning (5) Lost MDD Timeout
Jun 12 2020 21:56:49 Critical (3) No Ranging Response received - T3 time-out
Jun 12 2020 21:57:16 Warning (5) Lost MDD Timeout
Jun 12 2020 22:04:26 Critical (3) No Ranging Response received - T3 time-out
Jun 12 2020 22:05:47 Warning (5) Lost MDD Timeout
Jun 12 2020 23:22:23 Critical (3) No Ranging Response received - T3 time-out
Jun 12 2020 23:23:54 Warning (5) Lost MDD Timeout
Jun 12 2020 23:26:13 Critical (3) No Ranging Response received - T3 time-out
Jun 12 2020 23:36:07 Warning (5) Lost MDD Timeout
Jun 12 2020 23:49:03 Critical (3) No Ranging Response received - T3 time-out
Jun 12 2020 23:49:57 Warning (5) Lost MDD Timeout
Jun 13 2020 00:55:35 Critical (3) No Ranging Response received - T3 time-out
Jun 13 2020 01:13:58 Warning (5) Lost MDD Timeout
Jun 13 2020 01:39:22 Critical (3) No Ranging Response received - T3 time-out
Jun 13 2020 01:57:15 Warning (5) Lost MDD Timeout
Jun 13 2020 02:07:53 Critical (3) No Ranging Response received - T3 time-out
Jun 13 2020 02:12:50 Warning (5) Lost MDD Timeout
Jun 13 2020 03:01:08 Critical (3) No Ranging Response received - T3 time-out
Jun 13 2020 03:45:09 Warning (5) Lost MDD Timeout
Jun 13 2020 04:07:40 Critical (3) No Ranging Response received - T3 time-out
Jun 13 2020 04:47:30 Warning (5) Lost MDD Timeout
Jun 13 2020 05:06:36 Critical (3) No Ranging Response received - T3 time-out
Jun 13 2020 05:26:25 Warning (5) Lost MDD Timeout
Jun 13 2020 05:57:57 Critical (3) No Ranging Response received - T3 time-out
Jun 13 2020 05:59:06 Warning (5) Lost MDD Timeout
Jun 13 2020 06:20:48 Critical (3) No Ranging Response received - T3 time-out
Jun 13 2020 06:23:50 Warning (5) Lost MDD Timeout
Jun 13 2020 06:39:49 Critical (3) No Ranging Response received - T3 time-out
Jun 13 2020 06:40:30 Warning (5) Lost MDD Timeout
Jun 13 2020 08:14:52 Critical (3) No Ranging Response received - T3 time-out
Jun 13 2020 08:22:30 Warning (5) Lost MDD Timeout
Jun 13 2020 08:45:19 Critical (3) No Ranging Response received - T3 time-out
Jun 13 2020 08:45:37 Warning (5) Lost MDD Timeout
Jun 13 2020 08:49:08 Critical (3) No Ranging Response received - T3 time-out
Jun 13 2020 08:49:08 Warning (5) Lost MDD Timeout

 

Power Levels:

<tabindex=-1>Startup Procedure</tabindex=-1>
Procedure Status Comment
Acquire Downstream Channel 597000000 Hz Locked
Connectivity State Ok Operational
Boot State Ok Operational
Security Enabled BPI+
IP Provisioning Mode Honor MDD honorMdd(4)
Downstream Bonded Channels (Partial Service)
Channel Lock Status Modulation Channel ID Frequency Power SNR Correctables UnCorrectables
1 Locked QAM 256 38 405000000 Hz -0.5 dBmV 36.3 dB 136724 44194
2 Locked QAM 256 39 411000000 Hz -0.5 dBmV 36.3 dB 136408 38591
3 Locked QAM 256 40 417000000 Hz -0.5 dBmV 35.7 dB 149200 40426
4 Locked QAM 256 41 423000000 Hz -0.7 dBmV 36.6 dB 1962769 749229
5 Locked QAM 256 42 429000000 Hz -0.5 dBmV 37.6 dB 913337 2478524
6 Locked QAM 256 43 435000000 Hz -1.0 dBmV 37.3 dB 980693 2812523
7 Locked QAM 256 44 441000000 Hz -1.4 dBmV 37.3 dB 771913 50376
8 Locked QAM 256 45 447000000 Hz -1.5 dBmV 37.3 dB 841399 37366
9 Locked QAM 256 34 453000000 Hz -1.4 dBmV 37.3 dB 183495 35707
10 Locked QAM 256 35 459000000 Hz -0.9 dBmV 37.6 dB 136490 35880
11 Locked QAM 256 36 465000000 Hz -0.5 dBmV 37.3 dB 98297 32788
12 Locked QAM 256 37 471000000 Hz 0.0 dBmV 36.3 dB 4741871 74725
13 Locked QAM 256 1 477000000 Hz 0.2 dBmV 32.9 dB 42610466 1645347
14 Locked QAM 256 2 483000000 Hz 0.2 dBmV 29.1 dB 119933551 33724511
15 Locked QAM 256 3 489000000 Hz 0.4 dBmV 35.0 dB 99504 26679
16 Locked QAM 256 4 495000000 Hz 0.0 dBmV 36.3 dB 118082 33143
17 Locked QAM 256 5 507000000 Hz -1.2 dBmV 36.6 dB 87330 24339
18 Locked QAM 256 6 513000000 Hz -1.2 dBmV 36.3 dB 82830 24579
19 Locked QAM 256 7 519000000 Hz -0.9 dBmV 31.4 dB 29178044 1710661
20 Locked QAM 256 8 525000000 Hz -0.2 dBmV 28.0 dB 349179632 19462589
21 Locked QAM 256 9 531000000 Hz -0.4 dBmV 32.5 dB 29741804 860985
22 Locked QAM 256 10 537000000 Hz -0.7 dBmV 36.6 dB 84102 28288
23 Locked QAM 256 11 543000000 Hz -1.5 dBmV 32.9 dB 82065 17155
24 Locked QAM 256 12 549000000 Hz -2.2 dBmV 33.4 dB 91652 16379
25 Locked QAM 256 13 555000000 Hz -2.5 dBmV 35.5 dB 90168 8402
26 Locked QAM 256 14 561000000 Hz -3.0 dBmV 36.2 dB 85271 9616
27 Locked QAM 256 15 567000000 Hz -2.9 dBmV 36.2 dB 24991 11401
28 Locked QAM 256 16 573000000 Hz -2.5 dBmV 36.6 dB 14999 12067
29 Locked QAM 256 17 579000000 Hz -2.2 dBmV 32.8 dB 14833459 424590
30 Locked QAM 256 18 585000000 Hz -1.7 dBmV 33.8 dB 18009 12085
31 Locked QAM 256 19 591000000 Hz -2.2 dBmV 32.0 dB 50055336 1773641
32 Locked QAM 256 20 597000000 Hz -3.0 dBmV 30.4 dB 30127280 2861595
Upstream Bonded Channels
Channel Lock Status US Channel Type Channel ID Symbol Rate Frequency Power
1 Locked ATDMA 8 5120 Ksym/sec 16600000 Hz 40.8 dBmV
2 Locked ATDMA 7 5120 Ksym/sec 23000000 Hz 45.5 dBmV
3 Locked ATDMA 6 5120 Ksym/sec 29400000 Hz 40.5 dBmV
4 Locked ATDMA 5 5120 Ksym/sec 35800000 Hz 42.0 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
 

 

My previous modem was a Motorola Surfboard that served as a router/modem combo. With the new CM700, I also setup a Ubiquiti Edgerouter X to handle routing and confirmed the speeds are still very low, even when connected directly to the modem. I initially believed it to be bad luck with new hardware, but the event log identifies similar errors to the old Surfboard and it makes me wonder there may be another underlying issue.

 

Has anyone else experienced these T3 timeouts coupled with poor internet performance? If so, did it persist after getting new hardware as it did for me? I'm not sure what my next troubleshooting steps should be.

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EG
Expert
‎06-13-2020 12:59 PM

Re: Poor Upload Speeds - T3 time-out

The SNR's are too low / out of spec on many of the downstream channels. Your line / connectivity still needs more work. I would get the techs out again. Good luck with it !



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