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Internet Drops Out Randomly

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Internet Drops Out Randomly

Hello, recently (about the past two months) I have been having a lot of internet drop outs. Normally it will drop out for a few seconds and come back. Unfortunately this is long enough to have issues with a live stream or if I am connected to my work VPN. Sometimes it will drop out for 10-15 minutes. It always seems to come back on its own althought during some of the longer dropouts I have forcefully restarted the modem, which does not seem to help or matter.

 

Sometimes I can go 1 to 2 days with everything working perfectly. Sometimes the internet will drop out every couple minutes. I have not found any rhyme or reason for predicting the outages. Sometimes it is in the morning. Sometimes in the evening. I have even had issues at 2-3am, which I would expect to be a very low demand time.

 

When the service is working if I run a speedtest, I get ~55 Mbps / 6 Mbps, which is about what I expect considering I have 60/10 service. And if I ping 1000 times to 8.8.8.8 it has 0% packet loss with an average ping time of 10-20ms with a few spikes in the 80-100ms range. Overall not too bad. However, when the service is bad and I try the same ping test I see about 2-5% packet loss. I know ping is probably not the best test, but it is the easiest way for me to test the reliability.

 

This past Friday and Saturday were terrible (dropping about 1 minute every 5 minutes) so I did a bit of debugging. I tried the following:

 

1) Connected the modem directly to my computer to eliminate the router and/or wifi as a potential issue. No change, still about 2-5% packet loss with ping during this bad period.

 

2) Tried a different Ethernet cable from the modem. No change, still about 2-5% packet loss with ping during this bad period.

 

3) Tried a different computer. No change, still about 2-5% packet loss with ping during this bad period.

 

4) The main cable line comes into the house, goes to a splitter and then runs to my office. I tried connecting the modem directly off the splitter with a small 2-foot cable to eliminate the 30 foot cable run to the office. I tried a different splitter. I tried removing the splitter and connecting directly to the line coming into the house. No change, still about 2-5% packet loss with ping during this bad period.

 

5) I tried a different modem (D-link DCM301 and Arris SB6183). No change, still about 2-5% packet loss with ping during a bad period.

 

Is there anything else I can try? It seems like I have eliminated every variable I have control over. Also, here are the modem numbers with the normal connection (main line -> splitter -> office -> modem). Overall I think it looks okay. The receive power is a little high from what I have read, but it was ~11 dB when I was connected directly to the cable from the outside. There is no event page on the DCM301 that I can find.

 

Startup Procedure
Procedure Status Comment
Acquire Downstream Channel 585000000 Hz Locked
Connectivity State OK Operational
Boot State OK Operational
Configuration File OK  
Security Enabled BPI+

 

Downstream Bonded Channels
Channel Lock Status Modulation Channel ID Frequency Power SNR Correctables Uncorrectables
1 Locked QAM256 18 585000000 Hz 8.5 dB 40.9 dB 52 90
2 Locked QAM256 19 591000000 Hz 8.7 dB 41.4 dB 77 3
3 Locked QAM256 20 597000000 Hz 8.9 dB 41.2 dB 45 54
4 Locked QAM256 21 603000000 Hz 9.0 dB 40.9 dB 29 162
5 Locked QAM256 22 609000000 Hz 9.4 dB 41.3 dB 41 24
6 Locked QAM256 23 615000000 Hz 9.3 dB 40.8 dB 67 39
7 Locked QAM256 24 621000000 Hz 9.4 dB 41.3 dB 70 10
8 Locked QAM256 25 627000000 Hz 9.4 dB 40.8 dB 44 19

 

Upstream Bonded Channels
Channel Lock Status US Channel Type Channel ID Symbol Rate Frequency Power
1 Locked ATDMA 3 5120 Ksym/sec 22100000 Hz 45.8 dB
2 Locked ATDMA 1 5120 Ksym/sec 34900000 Hz 46.8 dB
3 Locked ATDMA 2 5120 Ksym/sec 28500000 Hz 46.8 dB
4 Locked ATDMA 4 5120 Ksym/sec 15700000 Hz 47.8 dB

 

Thank You!

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Expert

Re: Internet Drops Out Randomly

Would you please also post the modem's RF error /event log entries as well.



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Re: Internet Drops Out Randomly

The D-Link DCM301 is my main modem and unfortunately there is no event page/log.

 

The Arris SB6183 is the modem I borrowed from a friend for debugging. It probably only has ~24 hours on it. Here is what it has on the event log.

 

Time Priority Description
Time Not Established Critical (3) No Ranging Response received - T3 time-out
Fri Nov 08 09:59:16 2019 Critical (3) Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=f8:a0:97:b9:33:a8;CMTS-MAC=00:01:5c:63:3e:46;CM-QOS=1.1;CM-VER=3.0;
Fri Nov 08 10:00:36 2019 Critical (3) Resetting the cable modem due to docsDevResetNow
Time Not Established Critical (3) No Ranging Response received - T3 time-out
Sat Nov 09 06:43:26 2019 Critical (3) Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=f8:a0:97:b9:33:a8;CMTS-MAC=00:01:5c:63:3e:46;CM-QOS=1.1;CM-VER=3.0;
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Expert

Re: Internet Drops Out Randomly

Something may be going on but that really isn't enough log entries yet to be conclusive. See if they accumulate rapidly over the next 24 hours and please post the results again.



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Re: Internet Drops Out Randomly

The log did not change over about 24 hours. So I had a tech out today and they found the connections in the outside junction box had corroded. He replaced the connectors. So far so good.