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Smiggins's avatar
Smiggins
Aspirant
Aug 05, 2018

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

Troubleshooting

3 Replies

  • vkdelta's avatar
    vkdelta
    NETGEAR Employee Retired
    Aug 05, 2018

    is this is old installation and it has recently started doing this, then something has changed in your ISP signal.

     

    thats why you are seeing lots of T3 timeouts and one of the upstream line is completely disconnected (or very noisy) in the node causing 16 consecutive T3 timeouts. 

     

    have you changed anything in your connection in your home? Changed cables, connectors, splitters, etc

     

    If not, it is happening outside your home due to changes in network , addition of new lines for neigbors, etc

     

    • Smiggins's avatar
      Smiggins
      Aspirant
      Aug 05, 2018
      No I haven't changed anything. I get the feeling it's something outside. I live in a townhouse community and everyone has their own line while being in a small area. Plus the cable guys leave all kinds of buried crap in the ground.
      • vkdelta's avatar
        vkdelta
        NETGEAR Employee Retired
        Aug 05, 2018

        then it is outside. Get the line fixed.