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CM500 Cable Modem keeps losing connection

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CM500 Cable Modem keeps losing connection

Within the last week or 2 my CM500 modem has been losing connection and/or rebooting itself. It is doing it very frequently.

 

This is a log from today....

 

2018-8-5, 09:00:38    Critical (3)     Unicast Maintenance Ranging attempted - No response - Retries exhausted;CM-MAC=40:5d:82:40:2b:c8;CMTS-MAC=00:01:5c:81:9a:76;CM-QOS=1.1;CM-VER=3.0;

 

2018-8-5, 09:00:38    Critical (3)     16 consecutive T3 timeouts while trying to range on upstream channel 3;CM-MAC=40:5d:82:40:2b:c8;CMTS-MAC=00:01:5c:81:9a:76;CM-QOS=1.1;CM-VER=3.0;

 

2018-8-5, 09:00:39    Critical (3)     Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=40:5d:82:40:2b:c8;CMTS-MAC=00:01:5c:81:9a:76;CM-QOS=1.1;CM-VER=3.0;

 

2018-8-5, 09:01:07    Critical (3)     Unicast Maintenance Ranging attempted - No response - Retries exhausted;CM-MAC=40:5d:82:40:2b:c8;CMTS-MAC=00:01:5c:81:9a:76;CM-QOS=1.1;CM-VER=3.0;

 

2018-8-5, 09:01:07    Critical (3)     16 consecutive T3 timeouts while trying to range on upstream channel 2;CM-MAC=40:5d:82:40:2b:c8;CMTS-MAC=00:01:5c:81:9a:76;CM-QOS=1.1;CM-VER=3.0;

 

2018-8-5, 09:01:08    Critical (3)     Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=40:5d:82:40:2b:c8;CMTS-MAC=00:01:5c:81:9a:76;CM-QOS=1.1;CM-VER=3.0;

 

2018-8-5, 09:05:06    Critical (3)     Received Response to Broadcast Maintenance Request, But no Unicast Maintenance opportunities received - T4 time out;CM-MAC=40:5d:82:40:2b:c8;CMTS-MAC=00:01:5c:81:9a:76;CM-QOS=1.1;CM-VER=3.0;

 

2018-8-5, 09:05:37    Critical (3)     No Ranging Response received - T3 time-out;CM-MAC=40:5d:82:40:2b:c8;CMTS-MAC=00:01:5c:81:9a:76;CM-QOS=1.0;CM-VER=3.0;

 

1970-1-1, 00:00:21    Critical (3)     SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=40:5d:82:40:2b:c8;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.0;CM-VER=3.0;

 

1970-1-1, 00:00:25    Critical (3)     No Ranging Response received - T3 time-out;CM-MAC=40:5d:82:40:2b:c8;CMTS-MAC=00:01:5c:81:9a:76;CM-QOS=1.0;CM-VER=3.0;

 

2018-8-5, 10:14:48    Critical (3)     Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=40:5d:82:40:2b:c8;CMTS-MAC=00:01:5c:81:9a:76;CM-QOS=1.1;CM-VER=3.0;

 

2018-8-5, 10:15:56    Critical (3)     Unicast Maintenance Ranging attempted - No response - Retries exhausted;CM-MAC=40:5d:82:40:2b:c8;CMTS-MAC=00:01:5c:81:9a:76;CM-QOS=1.1;CM-VER=3.0;

 

2018-8-5, 10:15:56    Critical (3)     16 consecutive T3 timeouts while trying to range on upstream channel 2;CM-MAC=40:5d:82:40:2b:c8;CMTS-MAC=00:01:5c:81:9a:76;CM-QOS=1.1;CM-VER=3.0;

 

2018-8-5, 10:16:00    Critical (3)     Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=40:5d:82:40:2b:c8;CMTS-MAC=00:01:5c:81:9a:76;CM-QOS=1.1;CM-VER=3.0;

 

2018-8-5, 10:16:24    Critical (3)     Unicast Maintenance Ranging attempted - No response - Retries exhausted;CM-MAC=40:5d:82:40:2b:c8;CMTS-MAC=00:01:5c:81:9a:76;CM-QOS=1.1;CM-VER=3.0;

 

2018-8-5, 10:16:24    Critical (3)     16 consecutive T3 timeouts while trying to range on upstream channel 1;CM-MAC=40:5d:82:40:2b:c8;CMTS-MAC=00:01:5c:81:9a:76;CM-QOS=1.1;CM-VER=3.0;

 

2018-8-5, 10:16:24    Critical (3)     Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=40:5d:82:40:2b:c8;CMTS-MAC=00:01:5c:81:9a:76;CM-QOS=1.1;CM-VER=3.0;

 

2018-8-5, 10:20:40    Critical (3)     Received Response to Broadcast Maintenance Request, But no Unicast Maintenance opportunities received - T4 time out;CM-MAC=40:5d:82:40:2b:c8;CMTS-MAC=00:01:5c:81:9a:76;CM-QOS=1.1;CM-VER=3.0;

 

2018-8-5, 10:21:00    Critical (3)     No Ranging Response received - T3 time-out;CM-MAC=40:5d:82:40:2b:c8;CMTS-MAC=00:01:5c:81:9a:76;CM-QOS=1.0;CM-VER=3.0;

 

2018-8-5, 10:21:02    Critical (3)     Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=40:5d:82:40:2b:c8;CMTS-MAC=00:01:5c:81:9a:76;CM-QOS=1.0;CM-VER=3.0;

 

2018-8-5, 10:25:51    Critical (3)     Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=40:5d:82:40:2b:c8;CMTS-MAC=00:01:5c:81:9a:76;CM-QOS=1.1;CM-VER=3.0;

 

2018-8-5, 10:30:30    Critical (3)     Received Response to Broadcast Maintenance Request, But no Unicast Maintenance opportunities received - T4 time out;CM-MAC=40:5d:82:40:2b:c8;CMTS-MAC=00:01:5c:81:9a:76;CM-QOS=1.1;CM-VER=3.0;

 

2018-8-5, 10:30:51    Critical (3)     No Ranging Response received - T3 time-out;CM-MAC=40:5d:82:40:2b:c8;CMTS-MAC=00:01:5c:81:9a:76;CM-QOS=1.0;CM-VER=3.0;

 

2018-8-5, 10:30:57    Critical (3)     Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=40:5d:82:40:2b:c8;CMTS-MAC=00:01:5c:81:9a:76;CM-QOS=1.0;CM-VER=3.0;

 

2018-8-5, 10:37:28    Critical (3)     Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=40:5d:82:40:2b:c8;CMTS-MAC=00:01:5c:81:9a:76;CM-QOS=1.1;CM-VER=3.0;

 

2018-8-5, 10:42:07    Critical (3)     Received Response to Broadcast Maintenance Request, But no Unicast Maintenance opportunities received - T4 time out;CM-MAC=40:5d:82:40:2b:c8;CMTS-MAC=00:01:5c:81:9a:76;CM-QOS=1.1;CM-VER=3.0;

 

2018-8-5, 10:42:36    Critical (3)     No Ranging Response received - T3 time-out;CM-MAC=40:5d:82:40:2b:c8;CMTS-MAC=00:01:5c:81:9a:76;CM-QOS=1.0;CM-VER=3.0;

 

2018-8-5, 10:42:41    Critical (3)     Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=40:5d:82:40:2b:c8;CMTS-MAC=00:01:5c:81:9a:76;CM-QOS=1.0;CM-VER=3.0;

 

1970-1-1, 00:00:21    Critical (3)     SYNC Timing Synchronization failure - Failed to acquire FEC framing;CM-MAC=40:5d:82:40:2b:c8;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.0;CM-VER=3.0;

 

1970-1-1, 00:00:28    Notice (6)     Honoring MDD; IP provisioning mode = IPv6

 

2018-8-5, 13:02:58    Critical (3)     Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=40:5d:82:40:2b:c8;CMTS-MAC=00:01:5c:81:9a:76;CM-QOS=1.1;CM-VER=3.0;

 

2018-8-5, 13:04:06    Critical (3)     Unicast Maintenance Ranging attempted - No response - Retries exhausted;CM-MAC=40:5d:82:40:2b:c8;CMTS-MAC=00:01:5c:81:9a:76;CM-QOS=1.1;CM-VER=3.0;

 

2018-8-5, 13:04:06    Critical (3)     16 consecutive T3 timeouts while trying to range on upstream channel 3;CM-MAC=40:5d:82:40:2b:c8;CMTS-MAC=00:01:5c:81:9a:76;CM-QOS=1.1;CM-VER=3.0;

 

2018-8-5, 13:04:07    Critical (3)     Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=40:5d:82:40:2b:c8;CMTS-MAC=00:01:5c:81:9a:76;CM-QOS=1.1;CM-VER=3.0;

 

2018-8-5, 13:04:34    Critical (3)     Unicast Maintenance Ranging attempted - No response - Retries exhausted;CM-MAC=40:5d:82:40:2b:c8;CMTS-MAC=00:01:5c:81:9a:76;CM-QOS=1.1;CM-VER=3.0;

 

2018-8-5, 13:04:34    Critical (3)     16 consecutive T3 timeouts while trying to range on upstream channel 2;CM-MAC=40:5d:82:40:2b:c8;CMTS-MAC=00:01:5c:81:9a:76;CM-QOS=1.1;CM-VER=3.0;

 

2018-8-5, 13:08:33    Critical (3)     Received Response to Broadcast Maintenance Request, But no Unicast Maintenance opportunities received - T4 time out;CM-MAC=40:5d:82:40:2b:c8;CMTS-MAC=00:01:5c:81:9a:76;CM-QOS=1.1;CM-VER=3.0;

 

2018-8-5, 13:09:02    Critical (3)     No Ranging Response received - T3 time-out;CM-MAC=40:5d:82:40:2b:c8;CMTS-MAC=00:01:5c:81:9a:76;CM-QOS=1.0;CM-VER=3.0;

 

2018-8-5, 13:09:11    Critical (3)     Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=40:5d:82:40:2b:c8;CMTS-MAC=00:01:5c:81:9a:76;CM-QOS=1.0;CM-VER=3.0;

 

2018-8-5, 13:09:23    Notice (6)     Honoring MDD; IP provisioning mode = IPv6

 

 

Model: CM500|16x4 DOCSIS 3.0 Cable Modem

Expert

Re: CM500 Cable Modem keeps losing connection

Also post signal status. 

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




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New Poster

Re: CM500 Cable Modem keeps losing connection

Startup Procedure
Procedure     Status     Comment
Acquire Downstream Channel     471000000 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           33       471000000 Hz    -0.2 dBmV    40.1 dB      9                 58
2         Locked         QAM256           01       477000000 Hz    -0.3 dBmV    40.1 dB      0                 0
3         Locked         QAM256           10       531000000 Hz    -2.0 dBmV    39.2 dB      0                 0
4         Locked         QAM256           11       537000000 Hz    -2.1 dBmV    39.2 dB      0                 0
5         Locked         QAM256           15       561000000 Hz    -2.8 dBmV    38.7 dB      0                 0
6         Locked         QAM256           17       573000000 Hz    -2.7 dBmV    38.7 dB      0                 0
7         Locked         QAM256           22       603000000 Hz    -4.6 dBmV    37.2 dB      0                 0
8         Locked         QAM256           23       609000000 Hz    -5.5 dBmV    36.6 dB      0                 0
9         Locked         QAM256           24       615000000 Hz    -5.9 dBmV    36.2 dB      0                 0
10         Locked         QAM256           25       621000000 Hz    -5.5 dBmV    36.4 dB      0                 0
11         Locked         QAM256           26       627000000 Hz    -6.6 dBmV    35.6 dB      0                 0
12         Locked         QAM256           27       633000000 Hz    -8.1 dBmV    34.5 dB      0                 0
13         Locked         QAM256           28       639000000 Hz    -8.1 dBmV    33.7 dB      1                 0
14         Locked         QAM256           29       645000000 Hz    -6.6 dBmV    35.2 dB      1                 0
15         Locked         QAM256           30       651000000 Hz    -5.5 dBmV    33.9 dB      1                 0
16         Locked         QAM256           31       657000000 Hz    -5.4 dBmV    35.7 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    35800000 Hz    40.8 dBmV
2                Locked              ATDMA                 34       5120 Ksym/sec    29400000 Hz    40.8 dBmV
3                Locked              ATDMA                 35       5120 Ksym/sec    23000000 Hz    40.5 dBmV
4                Locked              ATDMA                 36       5120 Ksym/sec    16600000 Hz    40.3 dBmV
 
Current System Time:Sun Aug 05 18:00:21 2018
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