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Re: Help - dropping upstream connection

Frequent Visitor

Re: Help - dropping upstream connection

I think I am having similar problem.  Got upgraded from 300mbps to 1GBps about 5-6 weeks ago.  Swapped out comcast's modem for Netgear CM1150V modem.  First few weeks everything ran ok but in the last week or two internet would drop.  Only fix was rebooting the cable modem.  I have noticed the upstream link light blinks green when everything goes down.  My last cable modem was netgear and never dropped.  Now I am losing internet 1x to several times daily.

 

Called comcast they said my signals looked good when I spoke to them.  Here are my logs and status.  Is this a netgear issue, firwmare issue, xfinity issue?

 


Frequency start ValueThis field below allows you to modify the frequency the cable modem start with its scan during initialization and registration. Enter the new start frequency and restart the cable modem for it to take effect.

Starting Frequency
 

Startup Procedure

Procedure Status Comment
Acquire Downstream Channel 675000000 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 35 675000000 Hz 2.4 dBmV 41.9 dB 0 0
2 Locked QAM256 6 507000000 Hz 2.9 dBmV 43.3 dB 0 0
3 Locked QAM256 7 513000000 Hz 3.5 dBmV 43.4 dB 0 0
4 Locked QAM256 8 519000000 Hz 2.7 dBmV 43.1 dB 0 0
5 Locked QAM256 9 525000000 Hz 2.4 dBmV 43.1 dB 0 0
6 Locked QAM256 10 531000000 Hz 2.9 dBmV 43.1 dB 0 0
7 Locked QAM256 11 537000000 Hz 2.9 dBmV 43.3 dB 0 0
8 Locked QAM256 12 543000000 Hz 3.2 dBmV 43.3 dB 0 0
9 Locked QAM256 13 549000000 Hz 3.2 dBmV 43.4 dB 0 0
10 Locked QAM256 14 555000000 Hz 2.8 dBmV 43.2 dB 0 0
11 Locked QAM256 15 561000000 Hz 3.3 dBmV 43.3 dB 0 0
12 Locked QAM256 16 567000000 Hz 2.7 dBmV 43.2 dB 0 0
13 Locked QAM256 17 573000000 Hz 2.9 dBmV 43.2 dB 0 0
14 Locked QAM256 18 579000000 Hz 2.7 dBmV 43 dB 0 0
15 Locked QAM256 19 585000000 Hz 2.6 dBmV 43 dB 0 0
16 Locked QAM256 20 591000000 Hz 2.9 dBmV 43.1 dB 0 0
17 Locked QAM256 21 597000000 Hz 2.2 dBmV 42.9 dB 0 0
18 Locked QAM256 22 603000000 Hz 2.3 dBmV 42.9 dB 0 0
19 Locked QAM256 23 609000000 Hz 3.1 dBmV 43.1 dB 0 0
20 Locked QAM256 24 615000000 Hz 2 dBmV 42.6 dB 0 0
21 Locked QAM256 25 621000000 Hz 2.4 dBmV 42.7 dB 0 0
22 Locked QAM256 26 627000000 Hz 2.7 dBmV 42.9 dB 0 0
23 Locked QAM256 27 633000000 Hz 2 dBmV 42.7 dB 0 0
24 Locked QAM256 28 639000000 Hz 3 dBmV 42.9 dB 0 0
25 Locked QAM256 30 645000000 Hz 3.3 dBmV 43.1 dB 0 0
26 Locked QAM256 31 651000000 Hz 3.7 dBmV 43.2 dB 0 0
27 Locked QAM256 32 657000000 Hz 3.2 dBmV 42.9 dB 0 0
28 Locked QAM256 33 663000000 Hz 1.9 dBmV 42.5 dB 0 0
29 Locked QAM256 34 669000000 Hz 2.1 dBmV 42.5 dB 0 0
30 Locked QAM256 36 681000000 Hz 2.1 dBmV 42.5 dB 0 0
31 Locked QAM256 37 687000000 Hz 2.3 dBmV 42.5 dB 0 0
32 Not Locked Unknown 0 0 Hz 0.0 dBmV 0.0 dB 0 0
 

Upstream Bonded Channels

Channel Lock Status US Channel Type Channel ID Symbol Rate Frequency Power
1 Locked ATDMA 33 5120 Ksym/sec 36500000 Hz 44.8 dBmV
2 Locked ATDMA 34 5120 Ksym/sec 30100000 Hz 45 dBmV
3 Locked ATDMA 35 5120 Ksym/sec 23700000 Hz 45 dBmV
4 Locked ATDMA 36 5120 Ksym/sec 17300000 Hz 44.5 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
 

Downstream OFDM Channels

Channel Lock 
Status
Modulation / 
Profile ID
Channel 
ID
Frequency Power SNR / 
MER
Active Subcarrier 
Number Range
Unerrored 
Codewords
Correctable 
Codewords
Uncorrectable 
Codewords
1 Locked 0 29 693000000 Hz 1.2 dBmV 41.4 dB 1108 ~ 2987 9944982 1735 0
2 Not Locked 0 0 0 Hz 0 dBmV 0.0 dB 0 ~ 4095 0 0 0
 

Upstream OFDMA Channels

Channel Lock Status Modulation / Profile ID Channel ID Frequency Power
1 Not Locked 0 0 0 Hz 0 dBmV
2 Not Locked 0 0 0 Hz 0 dBmV
 

Current System Time:Tue Jul 16 10:23:26 2019System Up Time:01:20:32

 

 

Need to get this fixed.  Going on vacation and have security cams & smarthome that cannot access if modem goes down and nobody here to reboot.

 

Time Priority Description
Tue Jul 16 09:04:11 2019 Notice (6) TLV-11 - unrecognized OID;CM-MAC=28:80:88:00:67:d0;CMTS-MAC=00:01:5c:76:94:56;CM-QOS=1.1;CM-VER=3.1;
Time Not Established Notice (6) Honoring MDD; IP provisioning mode = IPv6
Time Not Established Critical (3) No Ranging Response received - T3 time-out;CM-MAC=28:80:88:00:67:d0;CMTS-MAC=00:01:5c:76:94:56;CM-QOS=1.1;CM-VER=3.1;
Time Not Established Critical (3) SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=28:80:88:00:67:d0;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.1;CM-VER=3.1;
Tue Jul 16 09:01:07 2019 Notice (6) CM-STATUS message sent. Event Type Code: 7; Chan ID: 34 36; DSID: N/A; MAC Addr: N/A; OFDM/OFDMA Profile ID: N/A.;CM-MAC=28:80:88:00:67:d0;CMTS-MAC=00:01:5c:76:94:56;CM-QOS=1.1;CM-VER=3.1;
Tue Jul 16 09:01:07 2019 Critical (3) Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=28:80:88:00:67:d0;CMTS-MAC=00:01:5c:76:94:56;CM-QOS=1.1;CM-VER=3.1;
Tue Jul 16 09:01:06 2019 Critical (3) 16 consecutive T3 timeouts while trying to range on upstream channel 3;CM-MAC=28:80:88:00:67:d0;CMTS-MAC=00:01:5c:76:94:56;CM-QOS=1.1;CM-VER=3.1;
Tue Jul 16 09:01:06 2019 Critical (3) Unicast Maintenance Ranging attempted - No response - Retries exhausted;CM-MAC=28:80:88:00:67:d0;CMTS-MAC=00:01:5c:76:94:56;CM-QOS=1.1;CM-VER=3.1;
Tue Jul 16 09:01:06 2019 Critical (3) Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=28:80:88:00:67:d0;CMTS-MAC=00:01:5c:76:94:56;CM-QOS=1.1;CM-VER=3.1;
Tue Jul 16 09:00:37 2019 Notice (6) CM-STATUS message sent. Event Type Code: 7; Chan ID: 34; DSID: N/A; MAC Addr: N/A; OFDM/OFDMA Profile ID: N/A.;CM-MAC=28:80:88:00:67:d0;CMTS-MAC=00:01:5c:76:94:56;CM-QOS=1.1;CM-VER=3.1;
Tue Jul 16 09:00:37 2019 Critical (3) Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=28:80:88:00:67:d0;CMTS-MAC=00:01:5c:76:94:56;CM-QOS=1.1;CM-VER=3.1;
Tue Jul 16 09:00:28 2019 Critical (3) 16 consecutive T3 timeouts while trying to range on upstream channel 0;CM-MAC=28:80:88:00:67:d0;CMTS-MAC=00:01:5c:76:94:56;CM-QOS=1.1;CM-VER=3.1;
Tue Jul 16 09:00:28 2019 Critical (3) Unicast Maintenance Ranging attempted - No response - Retries exhausted;CM-MAC=28:80:88:00:67:d0;CMTS-MAC=00:01:5c:76:94:56;CM-QOS=1.1;CM-VER=3.1;
Tue Jul 16 09:00:28 2019 Critical (3) Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=28:80:88:00:67:d0;CMTS-MAC=00:01:5c:76:94:56;CM-QOS=1.1;CM-VER=3.1;
Mon Jul 15 12:32:59 2019 Notice (6) CM-STATUS message sent. Event Type Code: 22; Chan ID: 29; DSID: N/A; MAC Addr: N/A; OFDM/OFDMA Profile ID: N/A.;CM-MAC=28:80:88:00:67:d0;CMTS-MAC=00:01:5c:76:94:56;CM-QOS=1.1;CM-VER=3.1;
Mon Jul 15 12:32:45 2019 Notice (6) TLV-11 - unrecognized OID;CM-MAC=28:80:88:00:67:d0;CMTS-MAC=00:01:5c:76:94:56;CM-QOS=1.1;CM-VER=3.1;
Mon Jul 15 12:32:36 2019 Notice (6) Honoring MDD; IP provisioning mode = IPv6
Mon Jul 15 12:32:31 2019 Critical (3) No Ranging Response received - T3 time-out;CM-MAC=28:80:88:00:67:d0;CMTS-MAC=00:01:5c:76:94:56;CM-QOS=1.1;CM-VER=3.1;
Mon Jul 15 12:32:20 2019 Critical (3) Received Response to Broadcast Maintenance Request, But no Unicast Maintenance opportunities received - T4 time out;CM-MAC=28:80:88:00:67:d0;CMTS-MAC=00:01:5c:76:94:56;CM-QOS=1.1;CM-VER=3.1;
Mon Jul 15 12:32:19 2019 Critical (3) Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=28:80:88:00:67:d0;CMTS-MAC=00:01:5c:76:94:56;CM-QOS=1.1;CM-VER=3.1;
Mon Jul 15 12:32:12 2019 Critical (3) Unicast Maintenance Ranging attempted - No response - Retries exhausted;CM-MAC=28:80:88:00:67:d0;CMTS-MAC=00:01:5c:76:94:56;CM-QOS=1.1;CM-VER=3.1;
Mon Jul 15 12:32:12 2019 Critical (3) Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=28:80:88:00:67:d0;CMTS-MAC=00:01:5c:76:94:56;CM-QOS=1.1;CM-VER=3.1;
Mon Jul 15 12:32:12 2019 Critical (3) Unicast Maintenance Ranging attempted - No response - Retries exhausted;CM-MAC=28:80:88:00:67:d0;CMTS-MAC=00:01:5c:76:94:56;CM-QOS=1.1;CM-VER=3.1;
Mon Jul 15 12:32:12 2019 Critical (3) Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=28:80:88:00:67:d0;CMTS-MAC=00:01:5c:76:94:56;CM-QOS=1.1;CM-VER=3.1;
Mon Jul 15 12:32:12 2019 Critical (3) Unicast Maintenance Ranging attempted - No response - Retries exhausted;CM-MAC=28:80:88:00:67:d0;CMTS-MAC=00:01:5c:76:94:56;CM-QOS=1.1;CM-VER=3.1;
Mon Jul 15 12:32:12 2019 Critical (3) Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=28:80:88:00:67:d0;CMTS-MAC=00:01:5c:76:94:56;CM-QOS=1.1;CM-VER=3.1;
Mon Jul 15 12:31:44 2019 Critical (3) SYNC Timing Synchronization failure - Loss of Sync;CM-MAC=28:80:88:00:67:d0;CMTS-MAC=00:01:5c:76:94:56;CM-QOS=1.1;CM-VER=3.1;
Mon Jul 15 12:31:43 2019 Notice (6) TLV-11 - unrecognized OID;CM-MAC=28:80:88:00:67:d0;CMTS-MAC=00:01:5c:76:94:56;CM-QOS=1.1;CM-VER=3.1;
Mon Jul 15 12:31:34 2019 Notice (6) Honoring MDD; IP provisioning mode = IPv6
Mon Jul 15 12:31:30 2019 Critical (3) No Ranging Response received - T3 time-out;CM-MAC=28:80:88:00:67:d0;CMTS-MAC=00:01:5c:76:94:56;CM-QOS=1.1;CM-VER=3.1;
Mon Jul 15 12:31:19 2019 Critical (3) Unicast Maintenance Ranging attempted - No response - Retries exhausted;CM-MAC=28:80:88:00:67:d0;CMTS-MAC=00:01:5c:76:94:56;CM-QOS=1.1;CM-VER=3.1;
Mon Jul 15 12:31:19 2019 Critical (3) Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=28:80:88:00:67:d0;CMTS-MAC=00:01:5c:76:94:56;CM-QOS=1.1;CM-VER=3.1;
Mon Jul 15 12:31:19 2019 Critical (3) Unicast Maintenance Ranging attempted - No response - Retries exhausted;CM-MAC=28:80:88:00:67:d0;CMTS-MAC=00:01:5c:76:94:56;CM-QOS=1.1;CM-VER=3.1;
Mon Jul 15 12:31:19 2019 Critical (3) Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=28:80:88:00:67:d0;CMTS-MAC=00:01:5c:76:94:56;CM-QOS=1.1;CM-VER=3.1;
Mon Jul 15 12:31:19 2019 Critical (3) Unicast Maintenance Ranging attempted - No response - Retries exhausted;CM-MAC=28:80:88:00:67:d0;CMTS-MAC=00:01:5c:76:94:56;CM-QOS=1.1;CM-VER=3.1;
Mon Jul 15 12:31:19 2019 Critical (3) Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=28:80:88:00:67:d0;CMTS-MAC=00:01:5c:76:94:56;CM-QOS=1.1;CM-VER=3.1;
Mon Jul 15 12:31:19 2019 Critical (3) Unicast Maintenance Ranging attempted - No response - Retries exhausted;CM-MAC=28:80:88:00:67:d0;CMTS-MAC=00:01:5c:76:94:56;CM-QOS=1.1;CM-VER=3.1;
Mon Jul 15 12:31:19 2019 Critical (3) Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=28:80:88:00:67:d0;CMTS-MAC=00:01:5c:76:94:56;CM-QOS=1.1;CM-VER=3.1;
Mon Jul 15 12:30:51 2019 Critical (3) SYNC Timing Synchronization failure - Loss of Sync;CM-MAC=28:80:88:00:67:d0;CMTS-MAC=00:01:5c:76:94:56;CM-QOS=1.1;CM-VER=3.1;
Mon Jul 15 12:30:46 2019 Notice (6)

TLV-11 - unrecognized OID;CM-MAC=28:80:88:00:67:d0;CMTS-MAC=00:01:5c:76:94:56;CM-QOS=1.1;CM-VER=3.1;

 

 

Highlighted
Official Employee

Re: Help - dropping upstream connection

Hi there. Sorry to hear about the trouble you're experiencing with your connection. I know how frustrating that can be! Based on the information that you provided, it does look like there are some signal issues present. Here is a great resource if you'd like to see for yourself: https://forums.xfinity.com/t5/Your-Home-Network/Xfinity-Internet-Connection-Troubleshooting-Tips/m-p.... Please go ahead and send me a private message with your name and I will be happy to help you out with this. It's very likely that we will need to get a technician out to the premise to resolve it. 

 

To send a private message, please click my name "ComcastMorgan" then select "Send a Message" on the right side.
 

Thank you!


I am an Official Comcast Employee.
Official Employees are from multiple teams within Comcast: CARE, Product, Leadership. We ask that you post publicly so people with similar questions may benefit from the conversation.
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Frequent Visitor

Re: Help - dropping upstream connection

Hi and thanks for responding.  I had a tech come out late last week. after I posted this.  When I had called in they found some "rippled" on a few of the channels so they sent him.  He found one line that was not shielded that the builder had put in. Once isolated we removed that from the splitter in my basement and the signal checked out strong, in range and normal.  

 

We thought this would fix it but within a day I had more drops.  I noticed they coincided with the use of Tivo Mini's but not consistently.  Seems hit or miss.  from what I read Tivo Moca could interfere with the Comcast GB service as a few of the channels on the cable modem may play in the same frequency range as Tivo using MocA.  Just curious if you heard of this and if there are any solutions.

 

I read somebody put a PoE filter on the input of the cable modem to shield any tivo signals coming in. However, my concern is that also blocks frequencies the cable modem needs itself to access and lock onto.

 

I will PM you my info now.

 

Official Employee

Re: Help - dropping upstream connection

Hi, marcNJ. I have been working with you along the way to continue with following through on ensuring we have reached a solution. I haven't heard back from you, so I assume everything is going well. I have completed this interaction, but please know that you're welcome to contact me directly via PM if you need further support on this from me. Thank you for being such a loyal customer of ours for many, many years. We appreciate you very much.


I am an Official Comcast Employee.
Official Employees are from multiple teams within Comcast: CARE, Product, Leadership. We ask that you post publicly so people with similar questions may benefit from the conversation.
Was your question answered? Mark the post as Best Answer!