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T3 and T4 timeouts

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T3 and T4 timeouts

Hi there, I have been having issues for weeks now with the internet dropping for 5-10 minutes multiple times a day.  It usually only happens in the morning, sometimes in the afternoon.  It has steadily become more and more of an issue.  The logs below are from my modem/router.  I am using a NETGEAR Gateway C6220.

 

TimePriorityDescription
2020-08-07, 12:09:58.0Warning (5)MDD message timeout;CM-MAC=08:02:8e:84:7b:70;CMTS-MAC=00:01:5c:83:c0:5f;CM-QOS=1.1;CM-VER=3.0;
2020-08-07, 12:09:05.0Notice (6)Honoring MDD; IP provisioning mode = IPv6
2020-08-07, 12:08:47.0Critical (3)Received Response to Broadcast Maintenance Request, But no Unicast Maintenance opportunities received - T4 time out;CM-MAC=08:02:8e:84:7b:70;CMTS-MAC=00:01:5c:83:c0:5f;CM-QOS=1.1;CM-VER=3.0;
2020-08-07, 10:48:25.0Critical (3)Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=08:02:8e:84:7b:70;CMTS-MAC=00:01:5c:83:c0:5f;CM-QOS=1.1;CM-VER=3.0;
2020-08-07, 10:48:25.0Critical (3)Unicast Maintenance Ranging attempted - No response - Retries exhausted;CM-MAC=08:02:8e:84:7b:70;CMTS-MAC=00:01:5c:83:c0:5f;CM-QOS=1.1;CM-VER=3.0;
2020-08-07, 10:48:25.0Critical (3)16 consecutive T3 timeouts while trying to range on upstream channel 3;CM-MAC=08:02:8e:84:7b:70;CMTS-MAC=00:01:5c:83:c0:5f;CM-QOS=1.1;CM-VER=3.0;
2020-08-07, 10:38:55.0Notice (6)Honoring MDD; IP provisioning mode = IPv6
2020-08-07, 10:38:39.0Critical (3)Received Response to Broadcast Maintenance Request, But no Unicast Maintenance opportunities received - T4 time out;CM-MAC=08:02:8e:84:7b:70;CMTS-MAC=00:01:5c:83:c0:5f;CM-QOS=1.1;CM-VER=3.0;
2020-08-07, 10:34:19.0Critical (3)Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=08:02:8e:84:7b:70;CMTS-MAC=00:01:5c:83:c0:5f;CM-QOS=1.1;CM-VER=3.0;

 

<tabindex=-1>Downstream Bonded Channels</tabindex=-1>
ChannelLock StatusModulationChannel IDFrequencyPowerSNRCorrectablesUncorrectables
1LockedQAM25621621000000 Hz-5.6 dBmV39.0 dB143300
2LockedQAM25622627000000 Hz-4.6 dBmV39.0 dB163261
3LockedQAM25623633000000 Hz-4.5 dBmV39.1 dB155267
4LockedQAM25624639000000 Hz-4.9 dBmV38.1 dB157245
5LockedQAM25625645000000 Hz-4.9 dBmV39.0 dB151355
6LockedQAM25626651000000 Hz-4.6 dBmV39.3 dB143137
7LockedQAM25627657000000 Hz-4.4 dBmV39.4 dB97156
8LockedQAM25628663000000 Hz-5.3 dBmV39.0 dB155130

<tabindex=-1>Upstream Bonded Channels</tabindex=-1>
ChannelLock StatusUS Channel TypeChannel IDSymbol RateFrequencyPower
1LockedATDMA55120 Ksym/sec35600000 Hz57.0 dBmV
2Not LockedUnknown00 Ksym/sec0 Hz0.0 dBmV
3Not LockedUnknown00 Ksym/sec0 Hz0.0 dBmV
4Not LockedUnknown00 Ksym/sec0 Hz0.0 dBmV

 

When I ran window diagnostics on the latest interruption, it said "windows can't communicate with the device or resource (primary dns server)"

 

EDIT: This occurs with both wired and wireless connections

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Frequent Visitor

Re: T3 and T4 timeouts

I'm having the same issue... I think we posted at about the same time.  It's also been much worse for me in the last month or so.

 

Not that I know anything or am any kind of expert (on anything) but your upstream level looks a bit high to me.  This usually means your modem is working harder and adding more power to get the signal out, at least that is my limited understanding.

 

If you are splitting the signal you could try removing the split and see if that number goes down.

 

Again, I don't really know anything but just stating what seemed to be the case for me.  My upstream numbers were creeping up to 55 so I removed the splitter the tech installed and now I don't see it go over 50.

 

I still have issues at the lower upstream levels though, so who knows.

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Expert

Re: T3 and T4 timeouts


@ibecker17 wrote:

Hi there, I have been having issues for weeks now with the internet dropping for 5-10 minutes multiple times a day.  It usually only happens in the morning, sometimes in the afternoon.  It has steadily become more and more of an issue.  The logs below are from my modem/router.  I am using a NETGEAR Gateway C6220.

 

TimePriorityDescription
2020-08-07, 12:09:58.0Warning (5)MDD message timeout;CM-MAC=08:02:8e:84:7b:70;CMTS-MAC=00:01:5c:83:c0:5f;CM-QOS=1.1;CM-VER=3.0;
2020-08-07, 12:09:05.0Notice (6)Honoring MDD; IP provisioning mode = IPv6
2020-08-07, 12:08:47.0Critical (3)Received Response to Broadcast Maintenance Request, But no Unicast Maintenance opportunities received - T4 time out;CM-MAC=08:02:8e:84:7b:70;CMTS-MAC=00:01:5c:83:c0:5f;CM-QOS=1.1;CM-VER=3.0;
2020-08-07, 10:48:25.0Critical (3)Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=08:02:8e:84:7b:70;CMTS-MAC=00:01:5c:83:c0:5f;CM-QOS=1.1;CM-VER=3.0;
2020-08-07, 10:48:25.0Critical (3)Unicast Maintenance Ranging attempted - No response - Retries exhausted;CM-MAC=08:02:8e:84:7b:70;CMTS-MAC=00:01:5c:83:c0:5f;CM-QOS=1.1;CM-VER=3.0;
2020-08-07, 10:48:25.0Critical (3)16 consecutive T3 timeouts while trying to range on upstream channel 3;CM-MAC=08:02:8e:84:7b:70;CMTS-MAC=00:01:5c:83:c0:5f;CM-QOS=1.1;CM-VER=3.0;
2020-08-07, 10:38:55.0Notice (6)Honoring MDD; IP provisioning mode = IPv6
2020-08-07, 10:38:39.0Critical (3)Received Response to Broadcast Maintenance Request, But no Unicast Maintenance opportunities received - T4 time out;CM-MAC=08:02:8e:84:7b:70;CMTS-MAC=00:01:5c:83:c0:5f;CM-QOS=1.1;CM-VER=3.0;
2020-08-07, 10:34:19.0Critical (3)Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=08:02:8e:84:7b:70;CMTS-MAC=00:01:5c:83:c0:5f;CM-QOS=1.1;CM-VER=3.0;

 

<tabindex=-1>Downstream Bonded Channels</tabindex=-1>
ChannelLock StatusModulationChannel IDFrequencyPowerSNRCorrectablesUncorrectables
1LockedQAM25621621000000 Hz-5.6 dBmV39.0 dB143300
2LockedQAM25622627000000 Hz-4.6 dBmV39.0 dB163261
3LockedQAM25623633000000 Hz-4.5 dBmV39.1 dB155267
4LockedQAM25624639000000 Hz-4.9 dBmV38.1 dB157245
5LockedQAM25625645000000 Hz-4.9 dBmV39.0 dB151355
6LockedQAM25626651000000 Hz-4.6 dBmV39.3 dB143137
7LockedQAM25627657000000 Hz-4.4 dBmV39.4 dB97156
8LockedQAM25628663000000 Hz-5.3 dBmV39.0 dB155130

<tabindex=-1>Upstream Bonded Channels</tabindex=-1>
ChannelLock StatusUS Channel TypeChannel IDSymbol RateFrequencyPower
1LockedATDMA55120 Ksym/sec35600000 Hz57.0 dBmV
2Not LockedUnknown00 Ksym/sec0 Hz0.0 dBmV
3Not LockedUnknown00 Ksym/sec0 Hz0.0 dBmV
4Not LockedUnknown00 Ksym/sec0 Hz0.0 dBmV

 

When I ran window diagnostics on the latest interruption, it said "windows can't communicate with the device or resource (primary dns server)"

 

EDIT: This occurs with both wired and wireless connections


The upstream power is way out of spec. The downstream power is on the low / weak side as well. That can cause random disconnects, spontaneous re-booting of the modem, speed, packet loss, latency problems, and the un-bonding of channels.

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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New Poster

Re: T3 and T4 timeouts

Thanks for the quick reply.  I live in an apartment building, but there are at least two valid coax connections that I know of, so I assume there are some splitters somewhere. Is their removal something I could handle on my own?  I am going to purchase another coax cable for my modem/router since that is definitely something I can do.  What brand recommendations do you have?

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New Poster

Re: T3 and T4 timeouts

Do you have any suggestions for replacing the coax cable?  Thanks!