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vebeltran's avatar
vebeltran
New Contributor II
2 years ago

T3 Timeouts

I've been experiencing frequent T3 timeouts and packet loss throughout the day on my Netgear CM1200. Had two techs come out so far to look at the issue, but each time they've said that everything loo...
connection issues
packet loss
vebeltran's avatar
vebeltran
New Contributor II

I'm not sure how much additional info this provides, but I was able to observe a lot of uncorrectable errors in the connection readout. Don't know if this helps shed any light on the what the issue might be.

Startup Procedure
Procedure Status Comment
Acquire Downstream Channel 753000000 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 29 753000000 Hz -3.2 dBmV 41.7 dB 70 168
2 Locked QAM256 1 117000000 Hz 4.4 dBmV 44.9 dB 1677 2079
3 Locked QAM256 2 123000000 Hz 4.4 dBmV 45.2 dB 2728 5254
4 Locked QAM256 3 129000000 Hz 4.6 dBmV 45.1 dB 1783 5349
5 Locked QAM256 4 135000000 Hz 4.4 dBmV 45.3 dB 1941 3392
6 Locked QAM256 5 141000000 Hz 4.1 dBmV 45.3 dB 1758 2942
7 Locked QAM256 6 147000000 Hz 3.9 dBmV 45.3 dB 1353 2158
8 Locked QAM256 7 153000000 Hz 3.8 dBmV 45.3 dB 1380 2072
9 Locked QAM256 8 159000000 Hz 3.8 dBmV 45.4 dB 1461 2593
10 Locked QAM256 9 165000000 Hz 3.9 dBmV 39 dB 1332 3092
11 Locked QAM256 10 171000000 Hz 3.8 dBmV 45.5 dB 1717 2259
12 Locked QAM256 11 177000000 Hz 3.9 dBmV 45.4 dB 5818 5268
13 Locked QAM256 12 183000000 Hz 3.9 dBmV 45.6 dB 4644 5054
14 Locked QAM256 13 189000000 Hz 3.8 dBmV 45.4 dB 1049 1562
15 Locked QAM256 14 195000000 Hz 3.9 dBmV 45.4 dB 2127 1424
16 Locked QAM256 15 201000000 Hz 3.9 dBmV 44.5 dB 3992 3557
17 Locked QAM256 16 207000000 Hz 3.9 dBmV 45.5 dB 2033 1292
18 Locked QAM256 17 213000000 Hz 3.9 dBmV 45.4 dB 831 1467
19 Locked QAM256 18 219000000 Hz 3.5 dBmV 45.5 dB 4268 2824
20 Locked QAM256 19 225000000 Hz 3.4 dBmV 45.3 dB 3491 2404
21 Locked QAM256 20 231000000 Hz 3.1 dBmV 45.3 dB 722 937
22 Locked QAM256 21 237000000 Hz 3.1 dBmV 45.3 dB 1783 803
23 Locked QAM256 22 243000000 Hz 2.9 dBmV 45.2 dB 2831 2545
24 Locked QAM256 23 249000000 Hz 2.9 dBmV 45.3 dB 1078 721
25 Locked QAM256 24 255000000 Hz 2.8 dBmV 45 dB 339 699
26 Locked QAM256 25 729000000 Hz -2.7 dBmV 42.1 dB 61 173
27 Locked QAM256 26 735000000 Hz -2.8 dBmV 41.8 dB 69 137
28 Locked QAM256 27 741000000 Hz -2.9 dBmV 41.5 dB 66 160
29 Locked QAM256 28 747000000 Hz -3.2 dBmV 41.7 dB 44 169
30 Locked QAM256 30 759000000 Hz -3.3 dBmV 41.8 dB 38 150
31 Locked QAM256 31 765000000 Hz -3.4 dBmV 41.7 dB 55 187
32 Locked QAM256 32 771000000 Hz -3.5 dBmV 41.5 dB 69 156
 
Upstream Bonded Channels
Channel Lock Status US Channel Type Channel ID Symbol Rate Frequency Power
1 Locked ATDMA 1 5120 Ksym/sec 36800000 Hz 37.5 dBmV
2 Locked ATDMA 2 5120 Ksym/sec 30400000 Hz 37.5 dBmV
3 Locked ATDMA 3 5120 Ksym/sec 24000000 Hz 37.5 dBmV
4 Locked ATDMA 4 5120 Ksym/sec 17600000 Hz 37 dBmV
5 Locked ATDMA 5 5120 Ksym/sec 60000000 Hz 39.3 dBmV
6 Locked ATDMA 6 5120 Ksym/sec 67000000 Hz 39.5 dBmV
7 Locked ATDMA 7 5120 Ksym/sec 74000000 Hz 40.3 dBmV
8 Locked ATDMA 8 5120 Ksym/sec 81000000 Hz 40.8 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 ,1 ,2 ,3 159 300000000 Hz 2.3 dBmV 45.4 dB 2216 ~ 5975 344825612 26438961 1526
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
WiderMouthOpen's avatar
WiderMouthOpen
Esteemed Contributor
2 years ago

Uncorrectables don't cause T3 errors. Uncorrectables are just packet loss and would slow down your connection but wouldn't disconnect it all together. A T3 can because it interrupts the connection between modem and router. I have a feeling this is a issue out on the street/pole.

  • vebeltran's avatar
    vebeltran
    New Contributor II
    2 years ago

    Ah got it. I am also seeing these in the logs before the T3s:

    Wed Jun 28 15:22:42 2023 Warning (5) Dynamic Range Window violation
    Wed Jun 28 15:22:42 2023 Warning (5) RNG-RSP CCAP Commanded Power in Excess of 6 dB Below the Value Corresponding to the Top of the DRW;CM-MAC=xx:xx:xx:xx:xx:xx;CMTS-MAC=xx:xx:xx:xx:xx:xx;CM-QOS=1.1;CM-VER=3.1;
    • WiderMouthOpen's avatar
      WiderMouthOpen
      Esteemed Contributor
      2 years ago

      With that said, uncorrectables are from noise on the downstream. T3 are caused by noise on the upstream. Maybe the same "leak" or point of ingress is causing the noise to effect both frequency sets.

    • WiderMouthOpen's avatar
      WiderMouthOpen
      Esteemed Contributor
      2 years ago

      The ones marked "critical" are what you want to watch out for.