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T3 timeout and Synchronization failure in modem logs

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Frequent Visitor

T3 timeout and Synchronization failure in modem logs

I've been losing internet connection and needed to reboot my modem a couple of times day since Friday. Noticed that the upstream light is blinking green on my Netgear CM500V modem right before I reboot it. I checked the logs for the modem and this is what i'm getting, doesn't make much since to me. Any help would be appreciated

 
TimePriorityDescription
Time Not EstablishedNotice (6)Honoring MDD; IP provisioning mode = IPv6
Time Not EstablishedCritical (3)No Ranging Response received - T3 time-out;CM-MAC=b0:39:56:ff:75:98;CMTS-MAC=00:01:5c:9e:a4:6a;CM-QOS=1.0;CM-VER=3.0;
Time Not EstablishedCritical (3)SYNC Timing Synchronization failure - Failed to acquire FEC framing;CM-MAC=b0:39:56:ff:75:98;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.0;CM-VER=3.0;
Sun Nov 01 06:53:21 2020Critical (3)16 consecutive T3 timeouts while trying to range on upstream channel 1;CM-MAC=b0:39:56:ff:75:98;CMTS-MAC=00:01:5c:9e:a4:6a;CM-QOS=1.1;CM-VER=3.0;
Sun Nov 01 06:53:21 2020Critical (3)Unicast Maintenance Ranging attempted - No response - Retries exhausted;CM-MAC=b0:39:56:ff:75:98;CMTS-MAC=00:01:5c:9e:a4:6a;CM-QOS=1.1;CM-VER=3.0;
Sun Nov 01 06:53:21 2020Critical (3)Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=b0:39:56:ff:75:98;CMTS-MAC=00:01:5c:9e:a4:6a;CM-QOS=1.1;CM-VER=3.0;
Sun Nov 01 06:53:19 2020Critical (3)Received Response to Broadcast Maintenance Request, But no Unicast Maintenance opportunities received - T4 time out;CM-MAC=b0:39:56:ff:75:98;CMTS-MAC=00:01:5c:9e:a4:6a;CM-QOS=1.1;CM-VER=3.0;
Sun Nov 01 06:27:19 2020Critical (3)Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=b0:39:56:ff:75:98;CMTS-MAC=00:01:5c:9e:a4:6a;CM-QOS=1.1;CM-VER=3.0;
Sun Nov 01 06:21:16 2020Critical (3)Received Response to Broadcast Maintenance Request, But no Unicast Maintenance opportunities received - T4 time out;CM-MAC=b0:39:56:ff:75:98;CMTS-MAC=00:01:5c:9e:a4:6a;CM-QOS=1.1;CM-VER=3.0;
Sun Nov 01 05:56:11 2020Critical (3)Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=b0:39:56:ff:75:98;CMTS-MAC=00:01:5c:9e:a4:6a;CM-QOS=1.1;CM-VER=3.0;
Sun Nov 01 05:55:16 2020Critical (3)Received Response to Broadcast Maintenance Request, But no Unicast Maintenance opportunities received - T4 time out;CM-MAC=b0:39:56:ff:75:98;CMTS-MAC=00:01:5c:9e:a4:6a;CM-QOS=1.1;CM-VER=3.0;
Sun Nov 01 05:50:56 2020Critical (3)Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=b0:39:56:ff:75:98;CMTS-MAC=00:01:5c:9e:a4:6a;CM-QOS=1.1;CM-VER=3.0;
Time Not EstablishedNotice (6)Honoring MDD; IP provisioning mode = IPv6
Time Not EstablishedCritical (3)No Ranging Response received - T3 time-out;CM-MAC=b0:39:56:ff:75:98;CMTS-MAC=00:01:5c:9e:a4:6a;CM-QOS=1.0;CM-VER=3.0;
Time Not EstablishedCritical (3)SYNC Timing Synchronization failure - Failed to acquire FEC framing;CM-MAC=b0:39:56:ff:75:98;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.0;CM-VER=3.0;
Time Not EstablishedNotice (6)Honoring MDD; IP provisioning mode = IPv6
Time Not EstablishedCritical (3)No Ranging Response received - T3 time-out;CM-MAC=b0:39:56:ff:75:98;CMTS-MAC=00:01:5c:9e:a4:6a;CM-QOS=1.0;CM-VER=3.0;
Time Not EstablishedCritical (3)SYNC Timing Synchronization failure - Failed to acquire FEC framing;CM-MAC=b0:39:56:ff:75:98;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.0;CM-VER=3.0;
Time Not EstablishedNotice (6)Honoring MDD; IP provisioning mode = IPv6
Time Not EstablishedCritical (3)No Ranging Response received - T3 time-out;CM-MAC=b0:39:56:ff:75:98;CMTS-MAC=00:01:5c:9e:a4:6a;CM-QOS=1.0;CM-VER=3.0;
Time Not EstablishedCritical (3)SYNC Timing Synchronization failure - Failed to acquire FEC framing;CM-MAC=b0:39:56:ff:75:98;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.0;CM-VER=3.0;
Time Not EstablishedNotice (6)Honoring MDD; IP provisioning mode = IPv6
Time Not EstablishedCritical (3)No Ranging Response received - T3 time-out;CM-MAC=b0:39:56:ff:75:98;CMTS-MAC=00:01:5c:9e:a4:6a;CM-QOS=1.0;CM-VER=3.0;
Time Not EstablishedCritical (3)SYNC Timing Synchronization failure - Failed to acquire FEC framing;CM-MAC=b0:39:56:ff:75:98;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.0;CM-VER=3.0;
Time Not EstablishedNotice (6)Honoring MDD; IP provisioning mode = IPv6
Time Not EstablishedCritical (3)No Ranging Response received - T3 time-out;CM-MAC=b0:39:56:ff:75:98;CMTS-MAC=00:01:5c:9e:a4:6a;CM-QOS=1.0;CM-VER=3.0;
Time Not EstablishedCritical (3)SYNC Timing Synchronization failure - Failed to acquire FEC framing;CM-MAC=b0:39:56:ff:75:98;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.0;CM-VER=3.0;
Time Not EstablishedNotice (6)Honoring MDD; IP provisioning mode = IPv6
Time Not EstablishedCritical (3)No Ranging Response received - T3 time-out;CM-MAC=b0:39:56:ff:75:98;CMTS-MAC=00:01:5c:9e:a4:6a;CM-QOS=1.0;CM-VER=3.0;
Time Not EstablishedCritical (3)SYNC Timing Synchronization failure - Failed to acquire FEC framing;CM-MAC=b0:39:56:ff:75:98;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.0;CM-VER=3.0;
Thu Oct 15 13:45:27 2020Critical (3)Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=b0:39:56:ff:75:98;CMTS-MAC=00:01:5c:9e:a4:6a;CM-QOS=1.1;CM-VER=3.0;
Thu Oct 15 13:45:49 2020Notice (6)Honoring MDD; IP provisioning mode = IPv6
Thu Oct 15 13:45:14 2020Critical (3)No Ranging Response received - T3 time-out;CM-MAC=b0:39:56:ff:75:98;CMTS-MAC=00:01:5c:9e:a4:6a;CM-QOS=1.0;CM-VER=3.0;
Thu Oct 15 13:44:07 2020Critical (3)Received Response to Broadcast Maintenance Request, But no Unicast Maintenance opportunities received - T4 time out;CM-MAC=b0:39:56:ff:75:98;CMTS-MAC=00:01:5c:9e:a4:6a;CM-QOS=1.1;CM-VER=3.0;
Thu Oct 15 13:42:53 2020Critical (3)SYNC Timing Synchronization failure - Failed to acquire FEC framing;CM-MAC=b0:39:56:ff:75:98;CMTS-MAC=00:01:5c:9e:a4:6a;CM-QOS=1.1;CM-VER=3.0;
Thu Oct 15 13:42:50 2020Critical (3)SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=b0:39:56:ff:75:98;CMTS-MAC=00:01:5c:9e:a4:6a;CM-QOS=1.1;CM-VER=3.0;
Thu Oct 15 13:41:14 2020Critical (3)SYNC Timing Synchronization failure - Failed to acquire FEC framing;CM-MAC=b0:39:56:ff:75:98;CMTS-MAC=00:01:5c:9e:a4:6a;CM-QOS=1.1;CM-VER=3.0;
Thu Oct 15 13:41:13 2020Critical (3)SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=b0:39:56:ff:75:98;CMTS-MAC=00:01:5c:9e:a4:6a;CM-QOS=1.1;CM-VER=3.0;
Thu Oct 15 13:41:05 2020Critical (3)SYNC Timing Synchronization failure - Failed to acquire FEC framing;CM-MAC=b0:39:56:ff:75:98;CMTS-MAC=00:01:5c:9e:a4:6a;CM-QOS=1.1;CM-VER=3.0;
Thu Oct 15 13:41:03 2020Critical (3)SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=b0:39:56:ff:75:98;CMTS-MAC=00:01:5c:9e:a4:6a;CM-QOS=1.1;CM-VER=3.0;

 

 
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Expert

Re: T3 timeout and Synchronization failure in modem logs

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




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Frequent Visitor

Re: T3 timeout and Synchronization failure in modem logs

Hopefully this is the info you are looking for, I don't see anything in my modem settings about SNR.

 

Downstream Bonded Channels
ChannelLock StatusModulationChannel IDFrequencyPowerSNRCorrectablesUncorrectables
1LockedQAM25632585000000 Hz1.3 dBmV41.7 dB468172
2LockedQAM25618489000000 Hz0.5 dBmV43.1 dB474311
3LockedQAM25619495000000 Hz0.5 dBmV43.1 dB476214
4LockedQAM25620507000000 Hz0.7 dBmV39.8 dB477226
5LockedQAM25621513000000 Hz1 dBmV42.9 dB498147
6LockedQAM25622519000000 Hz0.9 dBmV43 dB415262
7LockedQAM25623525000000 Hz0.9 dBmV42.9 dB419220
8LockedQAM25624531000000 Hz0.9 dBmV42.9 dB425234
9LockedQAM25625543000000 Hz1 dBmV43 dB480169
10LockedQAM25626549000000 Hz0.8 dBmV42.1 dB470169
11LockedQAM25627555000000 Hz0.9 dBmV39.3 dB456184
12LockedQAM25628561000000 Hz1 dBmV40.1 dB426223
13LockedQAM25629567000000 Hz0.9 dBmV42.1 dB440221
14LockedQAM25630573000000 Hz1.5 dBmV41.3 dB451199
15LockedQAM25631579000000 Hz1.5 dBmV40.5 dB458153
16LockedQAM25633591000000 Hz1.5 dBmV42.5 dB456180
 
Upstream Bonded Channels
ChannelLock StatusUS Channel TypeChannel IDSymbol RateFrequencyPower
1LockedATDMA35120 Ksym/sec30300000 Hz46 dBmV
2LockedATDMA15120 Ksym/sec17300000 Hz46 dBmV
3LockedATDMA25120 Ksym/sec23700000 Hz45.8 dBmV
4LockedATDMA45120 Ksym/sec36700000 Hz46.8 dBmV
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Expert

Re: T3 timeout and Synchronization failure in modem logs

The SNR's are being shown right there. 

The signal stats are o/k but the error log entries indicate that something is going on. Perhaps there is noise ingress into the line(s) somewhere.

 

There are other signal stat figures that can't be read by the modem. They are the "Upstream Rx Power" (Upstream Receive Power Level), the "Upstream SNR Ch." (Upstream Signal To Noise Ratio), and the "Upstream ICFR" (In Channel Frequency Response). These are as equally important in diagnosing connectivity issues as are the modem's stats.

 

I'm going to escalate your issue to the Comcast corporate employees that are available to these boards. They will be able to poll the CMTS to see whether or not everything is in the green zone, see your node / cable plant and modem health, and also see a history plot for the modem. You should get a reply here in your topic. Good luck !



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Frequent Visitor

Re: T3 timeout and Synchronization failure in modem logs

Great thanks for the quick response. Also this is a modem that I purchased.

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Official Employee

Re: T3 timeout and Synchronization failure in modem logs

Hi @gtribe

Thanks for using the Xfinity Forums to report your intermittent internet issues. I understand how frustrating this can be and want to help get this resolved. Can you send me a private message? To send a private message, click on my name, "ComcastChe," and then click send a message. Please include your first and last name and address.  


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Frequent Visitor

Re: T3 timeout and Synchronization failure in modem logs

HI ComcastChe,

 

I click on your name and saw your profile but don't see a link to send you a private message.

 

 

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Frequent Visitor

Re: T3 timeout and Synchronization failure in modem logs

ComcastCHE,

 

Sent you the private message with my info.

 

Thanks!

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Official Employee

Re: T3 timeout and Synchronization failure in modem logs

Thanks for sending your account details @gtribe! I've had the chance to reply to your private message and would like to start troubleshooting when you have time. Please reply at your earliest convenience, and we can get started! Chat with you soon 🙂  


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Frequent Visitor

Re: T3 timeout and Synchronization failure in modem logs

ComcastCHE,

 

I'm available to troubleshoot this issue. Also to let you know I contacted support by phone, they didn't find any issues but I did request a new modem which I'm receiving today just to rule out that is the issue.

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Official Employee

Re: T3 timeout and Synchronization failure in modem logs

OK, that is great to know! I have sent you a private message that should be in your inbox, so we can run through some tests. Talk to you soon!


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