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Motorola MB8600 frequent disconnects . Anyone else seeing this ?

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Motorola MB8600 frequent disconnects . Anyone else seeing this ?

I upgraded to Extreme 250 service a few weeks ago, and purchased a Motorola MB8600 modem to go with it.

 

I have experienced frequent Internet disconnects (every few days) ever since. The lights on the modem indicate that everything is fine (ie. Internet is up), but it is not. Powering down the modem and then back up has fixed the problem in every instance. I am getting really tired of doing so, however, and so is my husband.

 

Powering down the modem is not a workable solution for IoT device, such as our Wemo switches, electricity meter, solar meter, electric car chargers, etc, which we want to be able to use when we are physically away from home, possibly thousands of miles away, where power cycling the modem is not possible. We had no problems with the previous Arris SB6141 modem, but that modem was not supported for Extreme 250, so had to switch modem.

 

I still have a few days in my return window period for the MB8600. I believe the other option would be the more expensive Arris SB8200.

 

Are others seeing similar issues with the MB8600 ? I bought it because it was on the Comcast certified list, so I'm fairly disappointed.

 

 

Expert

Re: Motorola MB8600 frequent disconnects . Anyone else seeing this ?

Is there a router involved / WiFi ? If so, as a test, does a computer that is hardwired directly to the 8600 with an ethernet cable also lose its connection ?



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Re: Motorola MB8600 frequent disconnects . Anyone else seeing this ?

There is a wired router involved, Netgear R7000, and a separate Wifi access point, Orbi.

Both wired and wireless devices lose internet connection when this happens.

I haven't tried connecting a device directly to the modem - I wouldn't want to do so without there being any firewall.

I have tried resetting the wired router alone in the past on several occasions, and that did not solve the problem. Only resetting the modem did.

The router is the same as I had with my previous modem which never had this issue.

 

Expert

Re: Motorola MB8600 frequent disconnects . Anyone else seeing this ?


madbrain76 wrote:

 

I haven't tried connecting a device directly to the modem - I wouldn't want to do so without there being any firewall. 


So obviously the test can't be done unless you do so. All computers today have software firewalls built in to their operating systems, so it not a problem. Just be sure that it is enabled.

 

What do the modem's signal stats look like ? Try getting them here; http://192.168.100.1

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


 



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Re: Motorola MB8600 frequent disconnects . Anyone else seeing this ?

That test would only make sense to do when the internet is down, which it isn't at the moment.

 

Looks like I had a few minutes of outage this morning while I was asleep (got emails that my EV stations had gone offline!), but they came back online about 5 minutes later this time.

 

I am not able to access the modem's stats page from inside my LAN for some reason. I could access the previous modem's page, but not this one. I can ping the IP but HTTP is not responding.

 

I connected the PC directly to it and see these stats :

 

Connection
   Startup Sequence    
   Startup Step Status Comment

  
   Acquire Downstream Channel 591000000 Hz Locked
  
   Upstream Connection OK Operational
  
   Boot State OK Operational

  
   Configuration File OK d11_m_mb8600_extreme250_c01.cm
  
   Security Enabled BPI+
  


   Connection Status    
   System Up Time 0 days 11h:27m:36s.00  
  
   Network Access Allowed  
  


   Downstream Bonded Channels  
  
   Channel Lock Status Modulation Channel ID Freq. (MHz) Pwr (dBmV) SNR (d Corrected Uncorrected
1 Locked QAM256 14 591.0 7.5 39.2 278 41
2 Locked QAM256 1 513.0 8.2 39.9 500 581
3 Locked QAM256 2 519.0 7.8 39.9 479 566
4 Locked QAM256 3 525.0 7.6 39.8 117 0
5 Locked QAM256 4 531.0 7.5 39.8 477 532
6 Locked QAM256 5 537.0 7.5 39.9 363 460
7 Locked QAM256 6 543.0 7.3 39.9 512 531
8 Locked QAM256 7 549.0 7.5 39.0 443 445
9 Locked QAM256 8 555.0 7.6 39.7 518 434
10 Locked QAM256 9 561.0 7.7 39.4 613 629
11 Locked QAM256 10 567.0 7.7 38.9 2715 1384
12 Locked QAM256 11 573.0 7.9 39.7 546 545
13 Locked QAM256 12 579.0 7.9 39.8 585 594
14 Locked QAM256 13 585.0 7.6 39.5 111 0
15 Locked QAM256 15 597.0 7.4 39.4 111 0
16 Locked QAM256 16 603.0 7.3 39.6 919 563
17 Locked QAM256 17 609.0 7.3 39.7 81 0
18 Locked QAM256 18 615.0 7.2 38.4 242 2
19 Locked QAM256 19 621.0 7.3 39.1 82 0
20 Locked QAM256 20 627.0 7.2 39.6 808 579
21 Locked QAM256 21 633.0 7.3 39.1 865 795
22 Locked QAM256 22 639.0 7.3 39.3 71 0
23 Locked QAM256 23 645.0 7.3 39.6 416 471
24 Locked QAM256 24 651.0 6.8 38.6 507799 458240
25 Locked QAM256 26 681.0 6.1 39.4 615 460
26 Locked QAM256 27 687.0 6.0 39.0 747 458
27 Locked QAM256 28 693.0 5.8 39.1 742 580
28 Locked QAM256 29 699.0 5.8 39.3 899 508
29 Locked QAM256 30 705.0 6.0 39.4 715 753
30 Locked QAM256 31 717.0 5.8 39.2 961 604
31 Locked QAM256 32 723.0 5.3 39.0 672 660
32 Locked OFDM PLC 25 813.0 3.2 36.5 0 0


   Upstream Bonded Channels  
  
   Channel Lock Status Channel Type Channel ID Symb. Rate (Ksym/sec) Freq. (MHz) Pwr (dBmV)
1 Locked SC-QAM 1 5120 17.3 41.3
2 Locked SC-QAM 2 5120 23.7 41.5
3 Locked SC-QAM 3 5120 30.3 41.3
4 Locked SC-QAM 4 5120 36.7

40.8

 

Silver Problem Solver

Re: Motorola MB8600 frequent disconnects . Anyone else seeing this ?

You seem to have a lot of uncorrecteds on the downstream. I have a Netgear CM1000. Also D3.1, I found after a recent firmware update that the device locked on to a D3.0 channel as the starting freq. A factory reset got it locked back on to the D3.1 OFDM freq as the start.

No idea if that is the problem, or not, but it worked for me. Could well be something else in your local system or home wiring.

Contributor

Re: Motorola MB8600 frequent disconnects . Anyone else seeing this ?

Will try. No disconnects lately. But things are looking a lot worse signal wise. I only have one cable wire running into the house, and it was a brand new one that Comcast ran from the pole about 7 years ago. No other inside wiring. Either that one wire has gone bad, or there is a problem with the cable system, which is very possible given that I live on a hill and I am at the end of the street.

 comcast.png

Contributor

Experiencing a few minutes of downtime each day. Are those modem stats OK ?

I'm using a Motorola MB8600 on Extreme 250 since September. My house is the last one on the node, on top of a hill. I experience many short outages that wreak havoc with my 30+ iOT devices - Chromecasts audios, electric car chargers, solar meter, electric meter, etc. Typically it's 1-2 outages of 2-5 minutes each day. I have had the cable guy come twice already. Signal strength has improved , but the outages have not gone away completely. Comcast says they can't access my modem stats since I own it. Here are the latest stats :

comcast1129.png

Does this look like it's within specs ? What should acceptable numbers be ? No one in Comcast internet support can tell me.
Expert

Re: Experiencing a few minutes of downtime each day. Are those modem stats OK ?

The stats are o/k. The upstream power is a little on the low side but I'm not certain that it is the cause of your issue. It may be o/k for your particular local CMTS / system. The numbers are here;

 

http://forums.xfinity.com/t5/Your-Home-Network/Connection-Troubleshooting-Tips/m-p/1253575#M94474



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Contributor

Re: Experiencing a few minutes of downtime each day. Are those modem stats OK ?

Thanks. I just had another internet outage, and I was near the modem when it happened. All the lights remained in the normal state - ie. there was no physical signal disconnect at the modem level.

It seems the intermittent problem is between Comcast and the Internet, rather than between my home and Comcast ...

Contributor

URGENT : Re: Experiencing a few minutes of downtime each day. Are those modem stats OK ?

I setup Smokeping on my Raspberry Pi (wired device) to monitor my internet connection.

Turns out I have an average of 0.63% packet loss to the second Comcast hop (as shown in traceroute).

That is completely unacceptable, and certainly explains all of the problems I have been experiencing.

 

Is there anyone at Comcast who can help with this ? I'm using a Motorola MB8600 which is a certified modem.

Seems to me like either the modem or the Comcast network are the problem.

 

smokeping.png
Contributor

Re: Motorola MB8600 frequent disconnects . Anyone else seeing this ?

It is not home wiring. Cable guy already came 3x . Disconnects have continued. Packet loss to the internet is 0.63% average ccording to Smokeping. Either the modem or Comcast network is at fault.

 

smokeping.png
Expert
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Re: Motorola MB8600 frequent disconnects . Anyone else seeing this ?

New Poster

Re: Motorola MB8600 frequent disconnects . Anyone else seeing this ?

Yes, mine needs to be reset daily.