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Connection repeatedly dropping today

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Frequent Visitor

Connection repeatedly dropping today

My internet connection has dropped over a half dozen times throughout the day today.  I have a Netgear C7000v2.

 

Here are the power levels & noise info:

 

Startup Procedure
Procedure Status Comment
Acquire Downstream Channel 531000000 Hz Locked
Connectivity State OK Operational
Boot State OK Operational
Security Enabled BPI+
IP Provisioning Mode Honor MDD honorMdd(4)
 
Downstream Bonded Channels
Channel Lock Status Modulation Channel ID Frequency Power SNR Correctables Uncorrectables
1 Locked QAM256 9 531000000 Hz 1.6 dBmV 40.4 dB 2 0
2 Locked QAM256 38 429000000 Hz 3.5 dBmV 41.4 dB 0 0
3 Locked QAM256 39 435000000 Hz 2.9 dBmV 40.9 dB 0 0
4 Locked QAM256 40 441000000 Hz 3.3 dBmV 41 dB 0 0
5 Locked QAM256 41 447000000 Hz 3.2 dBmV 41.2 dB 1 0
6 Locked QAM256 34 453000000 Hz 2.9 dBmV 41 dB 0 0
7 Locked QAM256 35 459000000 Hz 2.7 dBmV 40.9 dB 0 0
8 Locked QAM256 36 465000000 Hz 2.7 dBmV 40.8 dB 0 0
9 Locked QAM256 37 471000000 Hz 3 dBmV 41.1 dB 1 0
10 Locked QAM256 1 477000000 Hz 2.6 dBmV 41.1 dB 1 0
11 Locked QAM256 2 483000000 Hz 2.6 dBmV 41.3 dB 2 0
12 Locked QAM256 3 489000000 Hz 2.4 dBmV 41.1 dB 1 0
13 Locked QAM256 4 495000000 Hz 2.7 dBmV 41.2 dB 2 0
14 Locked QAM256 5 507000000 Hz 2.2 dBmV 40.1 dB 1 0
15 Locked QAM256 6 513000000 Hz 2.2 dBmV 40.7 dB 5 0
16 Locked QAM256 7 519000000 Hz 2.2 dBmV 40.9 dB 6 0
17 Locked QAM256 8 525000000 Hz 2 dBmV 40.9 dB 0 0
18 Locked QAM256 10 537000000 Hz 1.9 dBmV 40.8 dB 0 0
19 Locked QAM256 11 543000000 Hz 1.5 dBmV 40.9 dB 0 0
20 Locked QAM256 12 549000000 Hz 1.4 dBmV 40.8 dB 0 0
21 Locked QAM256 13 555000000 Hz 0.8 dBmV 40.3 dB 0 0
22 Locked QAM256 14 561000000 Hz 1.1 dBmV 40.4 dB 0 0
23 Locked QAM256 15 567000000 Hz 0.7 dBmV 40.6 dB 0 0
24 Locked QAM256 16 573000000 Hz 0.4 dBmV 40.3 dB 0 0
 
Upstream Bonded Channels
Channel Lock Status US Channel Type Channel ID Symbol Rate Frequency Power
1 Locked ATDMA 63 5120 Ksym/sec 23000000 Hz 50.3 dBmV
2 Locked ATDMA 61 5120 Ksym/sec 35800000 Hz 50.3 dBmV
3 Locked ATDMA 62 5120 Ksym/sec 29400000 Hz 50.5 dBmV
4 Locked ATDMA 64 5120 Ksym/sec 16600000 Hz 51.5 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
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Frequent Visitor

Re: Connection repeatedly dropping today

Using PingPlotter, I also see very high packet loss (70% - 85%) from these two Comcast IPs:

 

2001:558:300:550::1

2001:558:3:73::2  (be-2411-pe11.350ecermak.il.ibone.comcast.net)

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Expert

Re: Connection repeatedly dropping today

The upstream power is too high and it may be intermittently fluctuating even higher to out of spec levels. That can cause random disconnects, spontaneous re-booting of the modem, speed, packet loss, and latency problems.

In a self troubleshooting effort to try to obtain better connectivity / more wiggle room, check to see if there are there any excess/unneeded coax cable splitters in the line leading to the modem that can be eliminated/re-configured. Any splitters that remain should be high quality and cable rated for 5-1002 MHz, bi-directional, and no gold colored garbage types like GE, RadioShack, RCA, Philips, Leviton, Magnavox, and Rocketfish from big box stores like Home Depot, Lowes, Target, Wal-Mart etc. Splitters should be swapped with known to be good / new ones to test

If there aren't any unneeded splitters that can be eliminated and if your coax wiring setup can't be reconfigured so that there is a single two way splitter connected directly off of the drop from the street/pole with one port feeding the modem and the other port feeding the rest of the house/equipment with additional splits as needed, and you've checked all the wiring and fittings for integrity and tightness and refresh them by taking them apart then check for and clean off any corrosion / oxidation on the center wire and put them back together again, then perhaps it's best to book a tech visit to investigate and correct.



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Frequent Visitor

Re: Connection repeatedly dropping today

Thank you so much for the insights!

 

I do have several splitters inside the house, but the good news is that I know how they're connected and can easily cut out all of the splitters and replace them with one-to-one connectors.

 

I'm having a hard time finding connectors that list the frequency range. Do you have any links to advice/recommendations? Happy to entertain specific product listings, retailer recommendations, etc.

 

I should be able to accomplish this with 2 connectors. Splitting isn't necessary. We use WiFi for media in the bedrooms.

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Expert

Re: Connection repeatedly dropping today

Do you mean like these ?;

 

https://www.amazon.com/Female-Coax-Cable-Joiner-Pack/dp/B001330WRE



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Re: Connection repeatedly dropping today

With 20 I could rewire the building, but if they look like the right fit, I'm not going to argue with $5.50!

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Expert

Re: Connection repeatedly dropping today

That was just a reference. See if you can find singles.



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Re: Connection repeatedly dropping today

A few new wrinkles in my saga.

 

I checked the lines inside, and there are no splitters in use. I was confused until I remembered that when I had my install, the tech spent A LOT of time tracking down the originating line and then eliminating splitters because he was concerned about line noise & signal quality. So the only connectors are those that were installed by the tech.

 

Things actually cleared up a bit yesteday, but here in the last hour the connection went really weird. Some sites worked just fine - Google, Facebook, XFinity. Others would not work at all - Reddit, Twitter, OpenDNS, and others.

 

My computer is connected with an Ethernet cable - brand new Cat7. So it's not a wireless issue.

 

I use PingPlotter and it's continually showing excessively large packet losses at 2001:558:300:550::1 - which it's been doing for a while. That's a Comcast DNS server. Seeing some sites work and others not seems to me a pretty strong indicator of DNS issues.

 

Seems to be a common thread in a few places. Is this a DNS server issue with Comcast? Would configuring the router to use an alternative DNS fix it?

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Expert

Re: Connection repeatedly dropping today


@rmdl73 wrote:

 

I use PingPlotter and it's continually showing excessively large packet losses at 2001:558:300:550::1 - which it's been doing for a while. That's a Comcast DNS server.


FWIW, Pinging the CC DNS servers is not a good test because they have them deliberately configured to de-prioritize / rate limit ICMP packet based ping probes. 





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Re: Connection repeatedly dropping today

I wondered that, suspected it might be the case but wanted to throw it out there just in case.

 

I've reconfigured the router to use OpenDNS, see if that has any impact.

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Frequent Visitor

Re: Connection repeatedly dropping today

After checking with the neighbors, service is sporadic for the entire building this morning. Some sites work (like this one), others don't (like XFinity's outage map).

 

https://www.xfinity.com/support/status  and https://www.xfinity.com/support/status-map will not load.

 

I've manually restarted the modem twice today (unplug, wait 30 seconds, plug in).

 

I tried calling and working through the automated system to get to an agent. The system wanted to do a modem reset (wouldn't let me proceed otherwise), so I did that. It then said that I had to wait 10 minutes to speak to an agent. I called back, and it put me on hold saying the reset was still in progress. Then it hung up on me.

 

I called back a few minutes later and it said I couldn't speak to an agent until I did a reset. Which it just did. Doesn't seem to be ANY way I can speak with someone to schedule a tech visit.

 

Could really use some help from XFinity. A callback would be appreciated.