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Network dropping sporadically, T3/T4 modem errors

Highlighted
Regular Visitor

Network dropping sporadically, T3/T4 modem errors

Hello. I'm having issues with my Netgear CM1000 modem (coupled with a TP-Link Archer C7 router) running on Comcast's gig internet service. Several times a day my modem will lose connectivity for ~7 minutes. On both wireless and wired connections to the router, LAN functionality is maintained, whereas the WAN is dropped. Looking into my modem logs I see errors corresponding to the connectivity loss. Below I've posted my channel info and the event log from the most recent outage. I greatly appreciate any help that can be offered and hope everyone's staying safe and healthy these days.

 

Startup Procedure

Procedure

Status

Comment

Acquire Downstream Channel

645000000 Hz

Locked

Connectivity State

OK

Operational

Boot State

OK

Operational

Security

Enable

BPI+

IP Provisioning Mode

Honor MDD

IPv6 only

 

   

 

Downstream Bonded Channels

 

Channel

Lock Status

Modulation

Channel ID

Frequency

Power

SNR / MER

Unerrored Codewords

Correctable Codewords

Uncorrectable Codewords

1

Locked

QAM256

30

645000000 Hz

2.0 dBmV

42.3 dB

523616232

140

535

2

Locked

QAM256

1

453000000 Hz

3.2 dBmV

43.3 dB

521463346

174

535

3

Locked

QAM256

2

459000000 Hz

3.2 dBmV

43.3 dB

521472164

117

551

4

Locked

QAM256

3

465000000 Hz

3.2 dBmV

43.0 dB

521479958

129

550

5

Locked

QAM256

4

471000000 Hz

3.1 dBmV

43.0 dB

521488395

129

553

6

Locked

QAM256

5

477000000 Hz

3.1 dBmV

42.7 dB

521495975

189

889

7

Locked

QAM256

6

483000000 Hz

2.9 dBmV

42.9 dB

521504431

128

535

8

Locked

QAM256

7

489000000 Hz

2.9 dBmV

43.0 dB

521511265

90

565

9

Locked

QAM256

8

495000000 Hz

3.1 dBmV

42.9 dB

521521494

121

547

10

Locked

QAM256

9

519000000 Hz

2.8 dBmV

42.6 dB

521528912

122

545

11

Locked

QAM256

10

525000000 Hz

2.8 dBmV

42.8 dB

521540020

117

565

12

Locked

QAM256

11

531000000 Hz

3.0 dBmV

42.9 dB

521547800

135

556

13

Locked

QAM256

12

537000000 Hz

3.0 dBmV

42.7 dB

521555368

117

559

14

Locked

QAM256

13

543000000 Hz

2.7 dBmV

42.9 dB

521565163

124

538

15

Locked

QAM256

14

549000000 Hz

2.4 dBmV

42.7 dB

521572499

108

548

16

Locked

QAM256

15

555000000 Hz

2.3 dBmV

42.7 dB

521581018

136

554

17

Locked

QAM256

16

561000000 Hz

2.5 dBmV

42.8 dB

521594277

121

538

18

Locked

QAM256

17

567000000 Hz

2.6 dBmV

42.7 dB

521602257

124

558

19

Locked

QAM256

18

573000000 Hz

2.4 dBmV

42.7 dB

521615289

109

549

20

Locked

QAM256

19

579000000 Hz

2.1 dBmV

42.8 dB

521623333

114

560

21

Locked

QAM256

20

585000000 Hz

2.1 dBmV

42.6 dB

521632884

132

551

22

Locked

QAM256

21

591000000 Hz

2.1 dBmV

42.5 dB

521640367

222

1102

23

Locked

QAM256

22

597000000 Hz

2.1 dBmV

42.6 dB

521648281

231

1015

24

Locked

QAM256

23

603000000 Hz

2.3 dBmV

42.7 dB

521657423

134

557

25

Locked

QAM256

24

609000000 Hz

2.1 dBmV

42.7 dB

521664845

149

534

26

Locked

QAM256

25

615000000 Hz

2.0 dBmV

42.5 dB

521674185

129

550

27

Locked

QAM256

26

621000000 Hz

2.4 dBmV

42.8 dB

521682035

129

553

28

Locked

QAM256

27

627000000 Hz

2.3 dBmV

42.5 dB

521690950

104

556

29

Locked

QAM256

28

633000000 Hz

2.1 dBmV

42.5 dB

521700453

132

548

30

Locked

QAM256

29

639000000 Hz

2.3 dBmV

42.5 dB

521704664

123

537

31

Locked

QAM256

31

651000000 Hz

1.6 dBmV

42.3 dB

521710084

134

548

32

Not Locked

Unknown

0

0 Hz

0.0 dBmV

0.0 dB

0

0

0

 

 

Upstream Bonded Channels

 

Channel

Lock Status

Modulation

Channel ID

Frequency

Power

1

Locked

ATDMA

5

36500000 Hz

37.8 dBmV

2

Locked

ATDMA

6

30100000 Hz

38.0 dBmV

3

Locked

ATDMA

7

23700000 Hz

37.0 dBmV

4

Locked

ATDMA

8

17300000 Hz

37.3 dBmV

5

Not Locked

Unknown

0

0 Hz

0.0 dBmV

6

Not Locked

Unknown

0

0 Hz

0.0 dBmV

7

Not Locked

Unknown

0

0 Hz

0.0 dBmV

8

Not Locked

Unknown

0

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

32

690000000 Hz

1.2 dBmV

40.3 dB

1108 ~ 2987

57936516

34453

2

2

Not Locked

0

0

0 Hz

0.2 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

Unknown

0

0 Hz

0 dBmV

2

Not Locked

Unknown

0

0 Hz

0 dBmV

 

 

Current System Time: Thu Mar 19 18:31:54 2020

 

System Up Time: 3:20:42

 

 

 

 

Time

Priority

Description

2020-03-19, 16:27:42

Notice (6)

Honoring MDD; IP provisioning mode = IPv6

2020-03-19, 16:27:04

Critical (3)

No Ranging Response received - T3 time-out;CM-MAC=28:80:88:ad:f1:18;CMTS-MAC=00:01:5c:b1:ee:5f;CM-QOS=1.1;CM-VER=3.1;

2020-03-19, 16:26:50

Critical (3)

Received Response to Broadcast Maintenance Request, But no Unicast Maintenance opportunities received - T4 time out;CM-MAC=28:80:88:ad:f1:18;CMTS-MAC=00:01:5c:b1:ee:5f;CM-QOS=1.1;CM-VER=3.1;

2020-03-19, 16:26:49

Critical (3)

No Ranging Response received - T3 time-out;CM-MAC=28:80:88:ad:f1:18;CMTS-MAC=00:01:5c:b1:ee:5f;CM-QOS=1.1;CM-VER=3.1;

2020-03-19, 16:26:48

Critical (3)

Received Response to Broadcast Maintenance Request, But no Unicast Maintenance opportunities received - T4 time out;CM-MAC=28:80:88:ad:f1:18;CMTS-MAC=00:01:5c:b1:ee:5f;CM-QOS=1.1;CM-VER=3.1;

2020-03-19, 16:25:17

Critical (3)

No Ranging Response received - T3 time-out;CM-MAC=28:80:88:ad:f1:18;CMTS-MAC=00:01:5c:b1:ee:5f;CM-QOS=1.1;CM-VER=3.1;

2020-03-19, 16:25:04

Notice (6)

CM-STATUS message sent. Event Type Code: 7; Chan ID: 5 6; DSID: N/A; MAC Addr: N/A; OFDM/OFDMA Profile ID: N/A.;CM-MAC=28:80:88:ad:f1:18;CMTS-MAC=00:01:5c:b1:ee:5f;CM-QOS=1.1;CM-VER=3.1;

2020-03-19, 16:24:59

Critical (3)

No Ranging Response received - T3 time-out;CM-MAC=28:80:88:ad:f1:18;CMTS-MAC=00:01:5c:b1:ee:5f;CM-QOS=1.1;CM-VER=3.1;

2020-03-19, 16:24:34

Notice (6)

CM-STATUS message sent. Event Type Code: 7; Chan ID: 5 6; DSID: N/A; MAC Addr: N/A; OFDM/OFDMA Profile ID: N/A.;CM-MAC=28:80:88:ad:f1:18;CMTS-MAC=00:01:5c:b1:ee:5f;CM-QOS=1.1;CM-VER=3.1;

2020-03-19, 16:24:04

Critical (3)

No Ranging Response received - T3 time-out;CM-MAC=28:80:88:ad:f1:18;CMTS-MAC=00:01:5c:b1:ee:5f;CM-QOS=1.1;CM-VER=3.1;

2020-03-19, 16:23:33

Notice (6)

CM-STATUS message sent. Event Type Code: 7; Chan ID: 5 6; DSID: N/A; MAC Addr: N/A; OFDM/OFDMA Profile ID: N/A.;CM-MAC=28:80:88:ad:f1:18;CMTS-MAC=00:01:5c:b1:ee:5f;CM-QOS=1.1;CM-VER=3.1;

2020-03-19, 16:23:05

Critical (3)

No Ranging Response received - T3 time-out;CM-MAC=28:80:88:ad:f1:18;CMTS-MAC=00:01:5c:b1:ee:5f;CM-QOS=1.1;CM-VER=3.1;

2020-03-19, 16:23:03

Notice (6)

CM-STATUS message sent. Event Type Code: 7; Chan ID: 5 6; DSID: N/A; MAC Addr: N/A; OFDM/OFDMA Profile ID: N/A.;CM-MAC=28:80:88:ad:f1:18;CMTS-MAC=00:01:5c:b1:ee:5f;CM-QOS=1.1;CM-VER=3.1;

2020-03-19, 16:22:54

Critical (3)

No Ranging Response received - T3 time-out;CM-MAC=28:80:88:ad:f1:18;CMTS-MAC=00:01:5c:b1:ee:5f;CM-QOS=1.1;CM-VER=3.1;

2020-03-19, 16:22:48

Critical (3)

Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=28:80:88:ad:f1:18;CMTS-MAC=00:01:5c:b1:ee:5f;CM-QOS=1.1;CM-VER=3.1;

2020-03-19, 16:22:48

Critical (3)

No Ranging Response received - T3 time-out;CM-MAC=28:80:88:ad:f1:18;CMTS-MAC=00:01:5c:b1:ee:5f;CM-QOS=1.1;CM-VER=3.1;

2020-03-19, 16:22:38

Critical (3)

Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=28:80:88:ad:f1:18;CMTS-MAC=00:01:5c:b1:ee:5f;CM-QOS=1.1;CM-VER=3.1;

2020-03-19, 16:22:38

Critical (3)

No Ranging Response received - T3 time-out;CM-MAC=28:80:88:ad:f1:18;CMTS-MAC=00:01:5c:b1:ee:5f;CM-QOS=1.1;CM-VER=3.1;

2020-03-19, 16:22:37

Critical (3)

Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=28:80:88:ad:f1:18;CMTS-MAC=00:01:5c:b1:ee:5f;CM-QOS=1.1;CM-VER=3.1;

2020-03-19, 16:22:37

Critical (3)

No Ranging Response received - T3 time-out;CM-MAC=28:80:88:ad:f1:18;CMTS-MAC=00:01:5c:b1:ee:5f;CM-QOS=1.1;CM-VER=3.1;

2020-03-19, 16:22:36

Critical (3)

Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=28:80:88:ad:f1:18;CMTS-MAC=00:01:5c:b1:ee:5f;CM-QOS=1.1;CM-VER=3.1;

2020-03-19, 16:22:35

Critical (3)

No Ranging Response received - T3 time-out;CM-MAC=28:80:88:ad:f1:18;CMTS-MAC=00:01:5c:b1:ee:5f;CM-QOS=1.1;CM-VER=3.1;

2020-03-19, 16:22:34

Critical (3)

Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=28:80:88:ad:f1:18;CMTS-MAC=00:01:5c:b1:ee:5f;CM-QOS=1.1;CM-VER=3.1;

2020-03-19, 16:22:34

Critical (3)

16 consecutive T3 timeouts while trying to range on upstream channel 0;CM-MAC=28:80:88:ad:f1:18;CMTS-MAC=00:01:5c:b1:ee:5f;CM-QOS=1.1;CM-VER=3.1;

2020-03-19, 16:22:34

Critical (3)

Unicast Maintenance Ranging attempted - No response - Retries exhausted;CM-MAC=28:80:88:ad:f1:18;CMTS-MAC=00:01:5c:b1:ee:5f;CM-QOS=1.1;CM-VER=3.1;

2020-03-19, 16:22:33

Critical (3)

Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=28:80:88:ad:f1:18;CMTS-MAC=00:01:5c:b1:ee:5f;CM-QOS=1.1;CM-VER=3.1;

2020-03-19, 16:22:33

Notice (6)

CM-STATUS message sent. Event Type Code: 7; Chan ID: 6; DSID: N/A; MAC Addr: N/A; OFDM/OFDMA Profile ID: N/A.;CM-MAC=28:80:88:ad:f1:18;CMTS-MAC=00:01:5c:b1:ee:5f;CM-QOS=1.1;CM-VER=3.1;

2020-03-19, 16:22:32

Critical (3)

Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=28:80:88:ad:f1:18;CMTS-MAC=00:01:5c:b1:ee:5f;CM-QOS=1.1;CM-VER=3.1;

2020-03-19, 16:22:23

Critical (3)

No Ranging Response received - T3 time-out;CM-MAC=28:80:88:ad:f1:18;CMTS-MAC=00:01:5c:b1:ee:5f;CM-QOS=1.1;CM-VER=3.1;

2020-03-19, 16:22:20

Critical (3)

Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=28:80:88:ad:f1:18;CMTS-MAC=00:01:5c:b1:ee:5f;CM-QOS=1.1;CM-VER=3.1;

2020-03-19, 16:22:20

Critical (3)

No Ranging Response received - T3 time-out;CM-MAC=28:80:88:ad:f1:18;CMTS-MAC=00:01:5c:b1:ee:5f;CM-QOS=1.1;CM-VER=3.1;

2020-03-19, 16:22:19

Critical (3)

Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=28:80:88:ad:f1:18;CMTS-MAC=00:01:5c:b1:ee:5f;CM-QOS=1.1;CM-VER=3.1;

2020-03-19, 16:22:18

Critical (3)

No Ranging Response received - T3 time-out;CM-MAC=28:80:88:ad:f1:18;CMTS-MAC=00:01:5c:b1:ee:5f;CM-QOS=1.1;CM-VER=3.1;

2020-03-19, 16:22:15

Critical (3)

Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=28:80:88:ad:f1:18;CMTS-MAC=00:01:5c:b1:ee:5f;CM-QOS=1.1;CM-VER=3.1;

2020-03-19, 16:22:15

Critical (3)

No Ranging Response received - T3 time-out;CM-MAC=28:80:88:ad:f1:18;CMTS-MAC=00:01:5c:b1:ee:5f;CM-QOS=1.1;CM-VER=3.1;

2020-03-19, 16:22:14

Critical (3)

Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=28:80:88:ad:f1:18;CMTS-MAC=00:01:5c:b1:ee:5f;CM-QOS=1.1;CM-VER=3.1;

2020-03-19, 16:22:14

Critical (3)

16 consecutive T3 timeouts while trying to range on upstream channel 1;CM-MAC=28:80:88:ad:f1:18;CMTS-MAC=00:01:5c:b1:ee:5f;CM-QOS=1.1;CM-VER=3.1;

2020-03-19, 16:22:14

Critical (3)

Unicast Maintenance Ranging attempted - No response - Retries exhausted;CM-MAC=28:80:88:ad:f1:18;CMTS-MAC=00:01:5c:b1:ee:5f;CM-QOS=1.1;CM-VER=3.1;

2020-03-19, 16:21:06

Critical (3)

Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=28:80:88:ad:f1:18;CMTS-MAC=00:01:5c:b1:ee:5f;CM-QOS=1.1;CM-VER=3.1;

Time Not Established

Notice (6)

Honoring MDD; IP provisioning mode = IPv6

 

Highlighted
Regular Visitor

Re: Network dropping sporadically, T3/T4 modem errors

Same thing happened last night; hoping someone can help me.  Thank you!

 

Time Priority Description
Time Not Established Notice (6) Honoring MDD; IP provisioning mode = IPv6
Time Not Established Critical (3) SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;CM-MAC=28:80:88:ad:f1:18;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.1;CM-VER=3.1;
2020-03-22, 23:23:18 Critical (3) No Ranging Response received - T3 time-out;CM-MAC=28:80:88:ad:f1:18;CMTS-MAC=00:01:5c:b1:ee:5f;CM-QOS=1.1;CM-VER=3.1;
2020-03-22, 23:23:05 Critical (3) Received Response to Broadcast Maintenance Request, But no Unicast Maintenance opportunities received - T4 time out;CM-MAC=28:80:88:ad:f1:18;CMTS-MAC=00:01:5c:b1:ee:5f;CM-QOS=1.1;CM-VER=3.1;
2020-03-22, 23:22:47 Critical (3) No Ranging Response received - T3 time-out;CM-MAC=28:80:88:ad:f1:18;CMTS-MAC=00:01:5c:b1:ee:5f;CM-QOS=1.1;CM-VER=3.1;
2020-03-22, 23:22:46 Critical (3) Received Response to Broadcast Maintenance Request, But no Unicast Maintenance opportunities received - T4 time out;CM-MAC=28:80:88:ad:f1:18;CMTS-MAC=00:01:5c:b1:ee:5f;CM-QOS=1.1;CM-VER=3.1;
2020-03-22, 23:22:45 Critical (3) No Ranging Response received - T3 time-out;CM-MAC=28:80:88:ad:f1:18;CMTS-MAC=00:01:5c:b1:ee:5f;CM-QOS=1.1;CM-VER=3.1;
2020-03-22, 23:22:44 Critical (3) Received Response to Broadcast Maintenance Request, But no Unicast Maintenance opportunities received - T4 time out;CM-MAC=28:80:88:ad:f1:18;CMTS-MAC=00:01:5c:b1:ee:5f;CM-QOS=1.1;CM-VER=3.1;
2020-03-22, 23:20:33 Critical (3) No Ranging Response received - T3 time-out;CM-MAC=28:80:88:ad:f1:18;CMTS-MAC=00:01:5c:b1:ee:5f;CM-QOS=1.1;CM-VER=3.1;
2020-03-22, 23:19:29 Critical (3) No Ranging Response received - T3 time-out;CM-MAC=28:80:88:ad:f1:18;CMTS-MAC=00:01:5c:b1:ee:5f;CM-QOS=1.1;CM-VER=3.1;
2020-03-22, 23:19:20 Critical (3) No Ranging Response received - T3 time-out;CM-MAC=28:80:88:ad:f1:18;CMTS-MAC=00:01:5c:b1:ee:5f;CM-QOS=1.1;CM-VER=3.1;
2020-03-22, 23:19:02 Critical (3) Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=28:80:88:ad:f1:18;CMTS-MAC=00:01:5c:b1:ee:5f;CM-QOS=1.1;CM-VER=3.1;
2020-03-22, 23:19:02 Critical (3) No Ranging Response received - T3 time-out;CM-MAC=28:80:88:ad:f1:18;CMTS-MAC=00:01:5c:b1:ee:5f;CM-QOS=1.1;CM-VER=3.1;
2020-03-22, 23:18:55 Critical (3) Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=28:80:88:ad:f1:18;CMTS-MAC=00:01:5c:b1:ee:5f;CM-QOS=1.1;CM-VER=3.1;
2020-03-22, 23:18:34 Critical (3) Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=28:80:88:ad:f1:18;CMTS-MAC=00:01:5c:b1:ee:5f;CM-QOS=1.1;CM-VER=3.1;
2020-03-22, 23:18:34 Critical (3) No Ranging Response received - T3 time-out;CM-MAC=28:80:88:ad:f1:18;CMTS-MAC=00:01:5c:b1:ee:5f;CM-QOS=1.1;CM-VER=3.1;
2020-03-22, 23:18:27 Critical (3) Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=28:80:88:ad:f1:18;CMTS-MAC=00:01:5c:b1:ee:5f;CM-QOS=1.1;CM-VER=3.1;
2020-03-22, 23:18:20 Critical (3) No Ranging Response received - T3 time-out;CM-MAC=28:80:88:ad:f1:18;CMTS-MAC=00:01:5c:b1:ee:5f;CM-QOS=1.1;CM-VER=3.1;
2020-03-22, 23:18:13 Critical (3) Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=28:80:88:ad:f1:18;CMTS-MAC=00:01:5c:b1:ee:5f;CM-QOS=1.1;CM-VER=3.1;
2020-03-22, 23:18:13 Critical (3) No Ranging Response received - T3 time-out;CM-MAC=28:80:88:ad:f1:18;CMTS-MAC=00:01:5c:b1:ee:5f;CM-QOS=1.1;CM-VER=3.1;
2020-03-22, 23:18:12 Critical (3) Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=28:80:88:ad:f1:18;CMTS-MAC=00:01:5c:b1:ee:5f;CM-QOS=1.1;CM-VER=3.1;
2020-03-22, 23:18:12 Critical (3) No Ranging Response received - T3 time-out;CM-MAC=28:80:88:ad:f1:18;CMTS-MAC=00:01:5c:b1:ee:5f;CM-QOS=1.1;CM-VER=3.1;
2020-03-22, 23:18:11 Critical (3) 16 consecutive T3 timeouts while trying to range on upstream channel 0;CM-MAC=28:80:88:ad:f1:18;CMTS-MAC=00:01:5c:b1:ee:5f;CM-QOS=1.1;CM-VER=3.1;
2020-03-22, 23:18:11 Critical (3) Unicast Maintenance Ranging attempted - No response - Retries exhausted;CM-MAC=28:80:88:ad:f1:18;CMTS-MAC=00:01:5c:b1:ee:5f;CM-QOS=1.1;CM-VER=3.1;
2020-03-22, 23:17:04 Critical (3) Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=28:80:88:ad:f1:18;CMTS-MAC=00:01:5c:b1:ee:5f;CM-QOS=1.1;CM-VER=3.1;
Highlighted
Regular Visitor

Re: Network dropping sporadically, T3/T4 modem errors

Posting my most recent event:

 

Time Priority Description
2020-03-25, 19:01:18 Notice (6) Honoring MDD; IP provisioning mode = IPv6
2020-03-25, 19:00:42 Critical (3) No Ranging Response received - T3 time-out;CM-MAC=28:80:88:ad:f1:18;CMTS-MAC=00:01:5c:b1:ee:5f;CM-QOS=1.1;CM-VER=3.1;
2020-03-25, 19:00:30 Critical (3) Received Response to Broadcast Maintenance Request, But no Unicast Maintenance opportunities received - T4 time out;CM-MAC=28:80:88:ad:f1:18;CMTS-MAC=00:01:5c:b1:ee:5f;CM-QOS=1.1;CM-VER=3.1;
2020-03-25, 19:00:23 Critical (3) No Ranging Response received - T3 time-out;CM-MAC=28:80:88:ad:f1:18;CMTS-MAC=00:01:5c:b1:ee:5f;CM-QOS=1.1;CM-VER=3.1;
2020-03-25, 19:00:21 Critical (3) Received Response to Broadcast Maintenance Request, But no Unicast Maintenance opportunities received - T4 time out;CM-MAC=28:80:88:ad:f1:18;CMTS-MAC=00:01:5c:b1:ee:5f;CM-QOS=1.1;CM-VER=3.1;
2020-03-25, 18:58:27 Critical (3) No Ranging Response received - T3 time-out;CM-MAC=28:80:88:ad:f1:18;CMTS-MAC=00:01:5c:b1:ee:5f;CM-QOS=1.1;CM-VER=3.1;
2020-03-25, 18:58:23 Notice (6) CM-STATUS message sent. Event Type Code: 7; Chan ID: 5 7; DSID: N/A; MAC Addr: N/A; OFDM/OFDMA Profile ID: N/A.;CM-MAC=28:80:88:ad:f1:18;CMTS-MAC=00:01:5c:b1:ee:5f;CM-QOS=1.1;CM-VER=3.1;
2020-03-25, 18:58:16 Critical (3) No Ranging Response received - T3 time-out;CM-MAC=28:80:88:ad:f1:18;CMTS-MAC=00:01:5c:b1:ee:5f;CM-QOS=1.1;CM-VER=3.1;
2020-03-25, 18:57:52 Notice (6) CM-STATUS message sent. Event Type Code: 7; Chan ID: 5 7; DSID: N/A; MAC Addr: N/A; OFDM/OFDMA Profile ID: N/A.;CM-MAC=28:80:88:ad:f1:18;CMTS-MAC=00:01:5c:b1:ee:5f;CM-QOS=1.1;CM-VER=3.1;
2020-03-25, 18:57:25 Critical (3) No Ranging Response received - T3 time-out;CM-MAC=28:80:88:ad:f1:18;CMTS-MAC=00:01:5c:b1:ee:5f;CM-QOS=1.1;CM-VER=3.1;
2020-03-25, 18:57:22 Notice (6) CM-STATUS message sent. Event Type Code: 7; Chan ID: 5 7; DSID: N/A; MAC Addr: N/A; OFDM/OFDMA Profile ID: N/A.;CM-MAC=28:80:88:ad:f1:18;CMTS-MAC=00:01:5c:b1:ee:5f;CM-QOS=1.1;CM-VER=3.1;
2020-03-25, 18:56:53 Critical (3) No Ranging Response received - T3 time-out;CM-MAC=28:80:88:ad:f1:18;CMTS-MAC=00:01:5c:b1:ee:5f;CM-QOS=1.1;CM-VER=3.1;
2020-03-25, 18:56:51 Notice (6) CM-STATUS message sent. Event Type Code: 7; Chan ID: 5 7; DSID: N/A; MAC Addr: N/A; OFDM/OFDMA Profile ID: N/A.;CM-MAC=28:80:88:ad:f1:18;CMTS-MAC=00:01:5c:b1:ee:5f;CM-QOS=1.1;CM-VER=3.1;
2020-03-25, 18:56:34 Critical (3) No Ranging Response received - T3 time-out;CM-MAC=28:80:88:ad:f1:18;CMTS-MAC=00:01:5c:b1:ee:5f;CM-QOS=1.1;CM-VER=3.1;
2020-03-25, 18:56:25 Critical (3) Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=28:80:88:ad:f1:18;CMTS-MAC=00:01:5c:b1:ee:5f;CM-QOS=1.1;CM-VER=3.1;
2020-03-25, 18:56:24 Critical (3) No Ranging Response received - T3 time-out;CM-MAC=28:80:88:ad:f1:18;CMTS-MAC=00:01:5c:b1:ee:5f;CM-QOS=1.1;CM-VER=3.1;
2020-03-25, 18:56:21 Critical (3) Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=28:80:88:ad:f1:18;CMTS-MAC=00:01:5c:b1:ee:5f;CM-QOS=1.1;CM-VER=3.1;
2020-03-25, 18:56:21 Notice (6) CM-STATUS message sent. Event Type Code: 7; Chan ID: 5 7; DSID: N/A; MAC Addr: N/A; OFDM/OFDMA Profile ID: N/A.;CM-MAC=28:80:88:ad:f1:18;CMTS-MAC=00:01:5c:b1:ee:5f;CM-QOS=1.1;CM-VER=3.1;
2020-03-25, 18:56:20 Critical (3) No Ranging Response received - T3 time-out;CM-MAC=28:80:88:ad:f1:18;CMTS-MAC=00:01:5c:b1:ee:5f;CM-QOS=1.1;CM-VER=3.1;
2020-03-25, 18:56:16 Critical (3) Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=28:80:88:ad:f1:18;CMTS-MAC=00:01:5c:b1:ee:5f;CM-QOS=1.1;CM-VER=3.1;
2020-03-25, 18:56:16 Critical (3) No Ranging Response received - T3 time-out;CM-MAC=28:80:88:ad:f1:18;CMTS-MAC=00:01:5c:b1:ee:5f;CM-QOS=1.1;CM-VER=3.1;
2020-03-25, 18:56:15 Critical (3) Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=28:80:88:ad:f1:18;CMTS-MAC=00:01:5c:b1:ee:5f;CM-QOS=1.1;CM-VER=3.1;
2020-03-25, 18:56:14 Critical (3) No Ranging Response received - T3 time-out;CM-MAC=28:80:88:ad:f1:18;CMTS-MAC=00:01:5c:b1:ee:5f;CM-QOS=1.1;CM-VER=3.1;
2020-03-25, 18:56:14 Critical (3) Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=28:80:88:ad:f1:18;CMTS-MAC=00:01:5c:b1:ee:5f;CM-QOS=1.1;CM-VER=3.1;
2020-03-25, 18:56:13 Critical (3) 16 consecutive T3 timeouts while trying to range on upstream channel 0;CM-MAC=28:80:88:ad:f1:18;CMTS-MAC=00:01:5c:b1:ee:5f;CM-QOS=1.1;CM-VER=3.1;
2020-03-25, 18:56:13 Critical (3) Unicast Maintenance Ranging attempted - No response - Retries exhausted;CM-MAC=28:80:88:ad:f1:18;CMTS-MAC=00:01:5c:b1:ee:5f;CM-QOS=1.1;CM-VER=3.1;
2020-03-25, 18:56:12 Critical (3) Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=28:80:88:ad:f1:18;CMTS-MAC=00:01:5c:b1:ee:5f;CM-QOS=1.1;CM-VER=3.1;
2020-03-25, 18:56:11 Critical (3) No Ranging Response received - T3 time-out;CM-MAC=28:80:88:ad:f1:18;CMTS-MAC=00:01:5c:b1:ee:5f;CM-QOS=1.1;CM-VER=3.1;
2020-03-25, 18:56:11 Critical (3) Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=28:80:88:ad:f1:18;CMTS-MAC=00:01:5c:b1:ee:5f;CM-QOS=1.1;CM-VER=3.1;
2020-03-25, 18:55:57 Critical (3) No Ranging Response received - T3 time-out;CM-MAC=28:80:88:ad:f1:18;CMTS-MAC=00:01:5c:b1:ee:5f;CM-QOS=1.1;CM-VER=3.1;
2020-03-25, 18:55:55 Critical (3) Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=28:80:88:ad:f1:18;CMTS-MAC=00:01:5c:b1:ee:5f;CM-QOS=1.1;CM-VER=3.1;
2020-03-25, 18:55:54 Critical (3) No Ranging Response received - T3 time-out;CM-MAC=28:80:88:ad:f1:18;CMTS-MAC=00:01:5c:b1:ee:5f;CM-QOS=1.1;CM-VER=3.1;
2020-03-25, 18:55:52 Critical (3) Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=28:80:88:ad:f1:18;CMTS-MAC=00:01:5c:b1:ee:5f;CM-QOS=1.1;CM-VER=3.1;
2020-03-25, 18:55:52 Critical (3) 16 consecutive T3 timeouts while trying to range on upstream channel 1;CM-MAC=28:80:88:ad:f1:18;CMTS-MAC=00:01:5c:b1:ee:5f;CM-QOS=1.1;CM-VER=3.1;
2020-03-25, 18:55:52 Critical (3) Unicast Maintenance Ranging attempted - No response - Retries exhausted;CM-MAC=28:80:88:ad:f1:18;CMTS-MAC=00:01:5c:b1:ee:5f;CM-QOS=1.1;CM-VER=3.1;
2020-03-25, 18:54:44 Critical (3) Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=28:80:88:ad:f1:18;CMTS-MAC=00:01:5c:b1:ee:5f;CM-QOS=1.1;CM-VER=3.1;
Highlighted
Expert

Re: Network dropping sporadically, T3/T4 modem errors

Even though the signal stats looked o/k at that snapshot in time, the error log entries confirm 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 can check the CMTS (Cable Modem Termination System) for any real time degradation and / or error reports, see your node / cable plant and modem health, and see whether or not everything is in the green zone. They can also see a history plot for the modem and poll for those upstream receive signal stats.



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I am a Customer Expert volunteering my time to help other customers here in the Forums.
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Highlighted
Official Employee

Re: Network dropping sporadically, T3/T4 modem errors

Hello NAROLD, thank you for taking the time out of your busy day to create a post. I'd be happy to run some test and check the local nodes to see what's going on. To better assist you could you please send me a private message with your full name by clicking on my name (ComcastAmir) and then click "Send a message"?


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!