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Frequent internet disconnection

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Regular Visitor

Frequent internet disconnection

Hi all, 

I am trying to figure out why our internet goes down multiple times per day, and in the evening, multiple times per hour. It takes up to 10 minutes usually to reconnect. 

I am using my own modem. I just installed a Motorola MB7621 24x8 modem. We previously had an Arris SB6190 (32x8), but it always seemed to stop working for hours any time the ambient temperature was >75 degrees. At least the Motorola doesn't go out for that long. I have checked all the connnections and they are all secure. Comcast/Xfinity did install a splitter underneath our house (which we don't need). 

 

I reset the modem last night, and in the first 21h45min I have had 36,192 corrected packets and 8,976 uncorrected packets on the downstream bonded channels. The power as of 11AM PDT ranges from -0.9 to 0.3 dBmV, and the signal to noise ranges between 37.4 and 43.5. 

 

For whatever reason, I only have one upstream bonded channel, with a power of 47.3 dBmV. 

 

The event log shows multiple critical errors over a 5 hour span:

-- Critical: "Received Response to Broadcast Maintenance Request, But no Unicast Mainenance opportunities received - T4 timeout"

-- Critical: "No ranging Response Received - T3 time-out"

-- Critical: "Started Unicast Maintenance Ranging - No response received - T3 timeout"

-- Critical: "Unicast Maintenance Ranging attempted - No response - Retries exhausted"

-- Critical: 16 consecutive T3 timeouts while trying to rangfe on upstream channel 3

-- Warning: Dynamic Range Window violation

 

My conclusion is that this is a problem with the signal to our house (single family home). Am I correct? Does anyone have any suggestions? Any help would be much appreciated. 

 

trying to add picts, don't know if they'll work:

Skeletor1687_0-1594576927820.png

Skeletor1687_1-1594576988699.png

 

 

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Expert

Re: Frequent internet disconnection

Can't see your pics. Since you are a new poster, they need to be approved by a Forum Admin. That could take some time. In the interim, you could try hosting them at one of those free third-party pic hosting sites like Imgur or Photobucket and post the link to them here.

Or copy all of the text of the status page and paste it into the body of your next post here.



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Regular Visitor

Re: Frequent internet disconnection

Hi and thank you for writing back. The tables are below. I will see if they are different in the evening. Also, I forgot to mention, my computer is connected via ethernet cable to my router / this is not a wi-fi issue. 

 

 System Up Time 1 days 21h:29m:14s  
 

 


  
   Network Access Allowed

 

Downstream:

Channel / Lock Status / Modulation / Channel ID / Freq. (MHz) / Pwr (dBmV) / SNR (dB) / Corrected / Uncorrected

1 Locked QAM256 24 549.0 1.5 42.9 2190 1659
2 Locked QAM256 25 555.0 1.4 42.6 3144 2003
3 Locked QAM256 26 561.0 1.3 42.7 2561 1337
4 Locked QAM256 27 567.0 1.5 42.7 2245 1450
5 Locked QAM256 28 573.0 1.6 42.8 2066 1439
6 Locked QAM256 29 579.0 1.8 42.9 2139 1168
7 Locked QAM256 30 585.0 1.9 41.0 2220 1276
8 Locked QAM256 31 591.0 1.8 42.5 3029 1571
9 Locked QAM256 32 597.0 1.9 42.9 3247 1358
10 Locked QAM256 33 603.0 1.6 42.6 6609 1828
11 Locked QAM256 34 609.0 1.5 42.4 3030 3018
12 Locked QAM256 35 615.0 1.2 42.3 2122 2348
13 Locked QAM256 36 621.0 1.3 42.4 1768 1186
14 Locked QAM256 37 627.0 1.3 42.4 1371 1080
15 Locked QAM256 38 633.0 1.2 42.4 1366 1046
16 Locked QAM256 39 639.0 1.5 42.2 1420 1236
17 Locked QAM256 40 645.0 1.8 43.5 2416 2617
18 Locked QAM256 41 651.0 1.8 43.3 3012 2657
19 Locked QAM256 42 657.0 1.7 43.4 3782 5118
20 Locked QAM256 43 663.0 1.8 43.6 3303 2814
21 Locked QAM256 44 669.0 1.7 43.4 5569 3930
22 Locked QAM256 45 675.0 1.6 43.5 1989 2069
23 Locked QAM256 46 681.0 1.6 43.5 2036 3551
24 Locked QAM256 47 687.0 1.3 43.5 2033 2550
Total             64667 50309

 

Upstream

   Channel Lock Status Channel Type Channel ID Symb. Rate (Ksym/sec) Freq. (MHz) Pwr (dBmV)
1 Locked ATDMA 8 5120 36.7 42.8
2 Not Locked Unknown 0 0 0 0.0
3 Not Locked Unknown 0 0 0 0.0
4 Not Locked Unknown 0 0 0 0.0
5 Not Locked Unknown 0 0 0 0.0
6 Not Locked Unknown 0 0 0 0.0
7 Not Locked Unknown 0 0 0 0.0
8 Not Locked Unknown 0 0 0 0.0

 

Highlighted
Regular Visitor

Re: Frequent internet disconnection

Also, here are the error messages: 

 Sun Jul 12 21:28:18 2020    Notice (6)   Honoring MDD; IP provisioning mode = IPv6 
 Sun Jul 12 22:45:28 2020    Critical (3)   Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=00:40:36:67:c0:2f;CMTS-MAC=00:01:5c:7a:d0:47;CM-QOS=1.1;CM-VER=3.0; 
 Sun Jul 12 22:45:28 2020    Critical (3)   Unicast Maintenance Ranging attempted - No response - Retries exhausted;CM-MAC=00:40:36:67:c0:2f;CMTS-MAC=00:01:5c:7a:d0:47;CM-QOS=1.1;CM-VER=3.0; 
 Sun Jul 12 22:45:28 2020    Critical (3)   16 consecutive T3 timeouts while trying to range on upstream channel 3;CM-MAC=00:40:36:67:c0:2f;CMTS-MAC=00:01:5c:7a:d0:47;CM-QOS=1.1;CM-VER=3.0; 
 Sun Jul 12 22:45:37 2020    Critical (3)   Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=00:40:36:67:c0:2f;CMTS-MAC=00:01:5c:7a:d0:47;CM-QOS=1.1;CM-VER=3.0; 
 Sun Jul 12 22:49:57 2020    Critical (3)   Received Response to Broadcast Maintenance Request, But no Unicast Maintenance opportunities received - T4 time out;CM-MAC=00:40:36:67:c0:2f;CMTS-MAC=00:01:5c:7a:d0:47;CM-QOS=1.1;CM-VER=3.0; 
 Sun Jul 12 22:50:31 2020    Critical (3)   No Ranging Response received - T3 time-out;CM-MAC=00:40:36:67:c0:2f;CMTS-MAC=00:01:5c:7a:d0:47;CM-QOS=1.0;CM-VER=3.0; 
 Sun Jul 12 22:50:41 2020    Notice (6)   Honoring MDD; IP provisioning mode = IPv6 
 Sun Jul 12 23:01:30 2020    Critical (3)   Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=00:40:36:67:c0:2f;CMTS-MAC=00:01:5c:7a:d0:47;CM-QOS=1.1;CM-VER=3.0; 
 Sun Jul 12 23:05:50 2020    Critical (3)   Received Response to Broadcast Maintenance Request, But no Unicast Maintenance opportunities received - T4 time out;CM-MAC=00:40:36:67:c0:2f;CMTS-MAC=00:01:5c:7a:d0:47;CM-QOS=1.1;CM-VER=3.0; 
 Sun Jul 12 23:06:16 2020    Critical (3)   No Ranging Response received - T3 time-out;CM-MAC=00:40:36:67:c0:2f;CMTS-MAC=00:01:5c:7a:d0:47;CM-QOS=1.0;CM-VER=3.0; 
 Sun Jul 12 23:06:23 2020    Notice (6)   Honoring MDD; IP provisioning mode = IPv6 
 Mon Jul 13 00:46:23 2020    Critical (3)   Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=00:40:36:67:c0:2f;CMTS-MAC=00:01:5c:7a:d0:47;CM-QOS=1.1;CM-VER=3.0; 
 Mon Jul 13 00:50:43 2020    Critical (3)   Received Response to Broadcast Maintenance Request, But no Unicast Maintenance opportunities received - T4 time out;CM-MAC=00:40:36:67:c0:2f;CMTS-MAC=00:01:5c:7a:d0:47;CM-QOS=1.1;CM-VER=3.0; 
 Mon Jul 13 00:51:16 2020    Notice (6)   Honoring MDD; IP provisioning mode = IPv6 
 Mon Jul 13 02:21:32 2020    Critical (3)   Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=00:40:36:67:c0:2f;CMTS-MAC=00:01:5c:7a:d0:47;CM-QOS=1.1;CM-VER=3.0; 
 Mon Jul 13 02:21:32 2020    Critical (3)   Unicast Maintenance Ranging attempted - No response - Retries exhausted;CM-MAC=00:40:36:67:c0:2f;CMTS-MAC=00:01:5c:7a:d0:47;CM-QOS=1.1;CM-VER=3.0; 
 Mon Jul 13 02:21:32 2020    Critical (3)   16 consecutive T3 timeouts while trying to range on upstream channel 3;CM-MAC=00:40:36:67:c0:2f;CMTS-MAC=00:01:5c:7a:d0:47;CM-QOS=1.1;CM-VER=3.0; 
 Mon Jul 13 02:22:02 2020    Critical (3)   Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=00:40:36:67:c0:2f;CMTS-MAC=00:01:5c:7a:d0:47;CM-QOS=1.1;CM-VER=3.0; 
 Mon Jul 13 02:22:02 2020    Critical (3)   Unicast Maintenance Ranging attempted - No response - Retries exhausted;CM-MAC=00:40:36:67:c0:2f;CMTS-MAC=00:01:5c:7a:d0:47;CM-QOS=1.1;CM-VER=3.0; 
 Mon Jul 13 02:22:02 2020    Critical (3)   16 consecutive T3 timeouts while trying to range on upstream channel 2;CM-MAC=00:40:36:67:c0:2f;CMTS-MAC=00:01:5c:7a:d0:47;CM-QOS=1.1;CM-VER=3.0; 
 Mon Jul 13 02:26:21 2020    Critical (3)   Received Response to Broadcast Maintenance Request, But no Unicast Maintenance opportunities received - T4 time out;CM-MAC=00:40:36:67:c0:2f;CMTS-MAC=00:01:5c:7a:d0:47;CM-QOS=1.1;CM-VER=3.0; 
 Mon Jul 13 02:26:45 2020    Critical (3)   No Ranging Response received - T3 time-out;CM-MAC=00:40:36:67:c0:2f;CMTS-MAC=00:01:5c:7a:d0:47;CM-QOS=1.0;CM-VER=3.0; 
 Mon Jul 13 02:27:52 2020    Critical (3)   Received Response to Broadcast Maintenance Request, But no Unicast Maintenance opportunities received - T4 time out;CM-MAC=00:40:36:67:c0:2f;CMTS-MAC=00:01:5c:7a:d0:47;CM-QOS=1.0;CM-VER=3.0; 
 Mon Jul 13 02:32:12 2020    Critical (3)   No Ranging Response received - T3 time-out;CM-MAC=00:40:36:67:c0:2f;CMTS-MAC=00:01:5c:7a:d0:47;CM-QOS=1.0;CM-VER=3.0; 
 Mon Jul 13 02:33:33 2020    Critical (3)   Received Response to Broadcast Maintenance Request, But no Unicast Maintenance opportunities received - T4 time out;CM-MAC=00:40:36:67:c0:2f;CMTS-MAC=00:01:5c:7a:d0:47;CM-QOS=1.0;CM-VER=3.0; 
 Mon Jul 13 02:33:53 2020    Critical (3)   No Ranging Response received - T3 time-out;CM-MAC=00:40:36:67:c0:2f;CMTS-MAC=00:01:5c:7a:d0:47;CM-QOS=1.0;CM-VER=3.0; 
 Mon Jul 13 02:34:56 2020    Critical (3)   Received Response to Broadcast Maintenance Request, But no Unicast Maintenance opportunities received - T4 time out;CM-MAC=00:40:36:67:c0:2f;CMTS-MAC=00:01:5c:7a:d0:47;CM-QOS=1.0;CM-VER=3.0; 
 Mon Jul 13 02:35:14 2020    Critical (3)   No Ranging Response received - T3 time-out;CM-MAC=00:40:36:67:c0:2f;CMTS-MAC=00:01:5c:7a:d0:47;CM-QOS=1.0;CM-VER=3.0; 
 Mon Jul 13 02:36:18 2020    Critical (3)   Received Response to Broadcast Maintenance Request, But no Unicast Maintenance opportunities received - T4 time out;CM-MAC=00:40:36:67:c0:2f;CMTS-MAC=00:01:5c:7a:d0:47;CM-QOS=1.0;CM-VER=3.0; 
 Mon Jul 13 02:36:35 2020    Critical (3)   No Ranging Response received - T3 time-out;CM-MAC=00:40:36:67:c0:2f;CMTS-MAC=00:01:5c:7a:d0:47;CM-QOS=1.0;CM-VER=3.0; 
 Mon Jul 13 02:36:52 2020    Notice (6)   Honoring MDD; IP provisioning mode = IPv6 
Highlighted
New Poster

Re: Frequent internet disconnection

This happens to us too. Our internet goes out probably 10-15 times per day, down from 20-30 with the "new" modem that we were sent. I was told they would send us an upgraded version of the modem but it is exactly the same as the old one. If they say that you need to switch to an Xfinity modem, you don't. The service is trash either way. If there was any other internet provider where we live, I would have switched a month ago when we signed up. This is the worst service I have ever had and their customer service is a joke. They never have real solutions and avoid a real fix. So sorry you're dealing with this too. It has made working from home a nightmare for me.

Highlighted
Regular Visitor

Re: Frequent internet disconnection

thanks. I wholeheartedly agree with you regarding the xfinity modem. If they tell me that's what I need then I'll go to a different provider; I fortunately have a choice (although unclear if any of the others are better). 

Highlighted
Regular Visitor

Re: Frequent internet disconnection

update: after several days of surprise stability, this problem recurred. I got on a chat with Xfinity -- and after my internet went out during the chat -- they seem to believe the problem has been solved. There troubleshooting said "there was corrupted data within the network and needed a refresh." the agent was unable to provide any more useful information. 

Highlighted
Regular Visitor

Re: Frequent internet disconnection

Further updates:

while xfinity's solution worked for a few days, once again the problem recurred

Chatting with them tonight they said, "since I am synchronizing all the settings on your modem so that it will be fully functional and fully operational. I successfully updated all the settings on your modem so that your internet connection will be stabilied into our system." 

I am doubtful this will work but will hold out a little hope

A neighbor posted to Nextdoor saying that when they talked to Xfinity (after trying 3 separate modems), Xfinity finally revealed to them that our node routinely operates at >85% capacity, which is why their internet has been unstable. They have not yet revealed this to me. 

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New Poster

Re: Frequent internet disconnection

Att fiber definitely more stable
Highlighted
Regular Contributor

Re: Frequent internet disconnection

There is probably a loose and/or corroded cable connection somewhere - maybe inside your house - maybe at the "demarc" outside your house - maybe somewhere beyond your demarc underground or on a pole or in one of those grey boxes by the side of the road.   

 

As far as I understand, every cable connector exposed to varying heat and humidity will inevitably loosen itself and corrode, requiring replacement and/or "cuttting cable nd re-crimping a new connector".

 

The timing of the failure is a clue as to whether the problem is HEAT or MOISTURE.

 

When failures occur dusk/nighttime that is when the cables/connectors are cooling and condensation will form, increasing impedance to the signal.       Problem in this case is MOISTURE along with temperature-cycling.  Tighten the connectors but note that the fix will be temporary at best - connection will require recrimp and new connector if any moisture/corrosion is visible whatsoever. 

 

When failures occur daytime/sunlight that is when cables/connectors are HOT and impedence increases.  Problem in this case is hopefully just the temperature cycling - if no moisture the connectors will not be corroded they will merely be LOOSE.  Tighten them.

 

It's always worse in summertime.