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Modem keeps dropping connection
I keep having problems with it randomly dropping and won’t come back up unless I reboot it. I have been fighting this for a while. ISP says nothing is wrong on there end. I’m at wits end with this so any help would be greatly appreciated. Here is the event logs from the modem.
Time Priority Description
1970-1-1, 00:01:06 Critical (3) SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=28:80:88:bc:0d:00;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.0;CM-VER=3.0;
1970-1-1, 00:01:12 Critical (3) No Ranging Response received - T3 time-out;CM-MAC=28:80:88:bc:0d:00;CMTS-MAC=00:c1:b1:61:06:3f;CM-QOS=1.0;CM-VER=3.0;
1970-1-1, 00:01:25 Critical (3) DHCP FAILED - Discover sent, no offer received;CM-MAC=28:80:88:bc:0d:00;CMTS-MAC=00:c1:b1:61:06:3f;CM-QOS=1.0;CM-VER=3.0;
1970-1-1, 00:00:20 Critical (3) SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=28:80:88:bc:0d:00;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.0;CM-VER=3.0;
1970-1-1, 00:00:23 Critical (3) SYNC Timing Synchronization failure - Failed to acquire FEC framing;CM-MAC=28:80:88:bc:0d:00;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.0;CM-VER=3.0;
1970-1-1, 00:00:25 Critical (3) SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=28:80:88:bc:0d:00;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.0;CM-VER=3.0;
1970-1-1, 00:00:44 Critical (3) SYNC Timing Synchronization failure - Failed to acquire FEC framing;CM-MAC=28:80:88:bc:0d:00;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.0;CM-VER=3.0;
1970-1-1, 00:01:01 Critical (3) No UCDs Received - Timeout;;CM-MAC=28:80:88:bc:0d:00;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.0;CM-VER=3.0;
1970-1-1, 00:01:02 Critical (3) SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=28:80:88:bc:0d:00;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.0;CM-VER=3.0;
1970-1-1, 00:01:10 Critical (3) No Ranging Response received - T3 time-out;CM-MAC=28:80:88:bc:0d:00;CMTS-MAC=00:c1:b1:61:06:3f;CM-QOS=1.0;CM-VER=3.0;
2019-9-10, 08:51:46 Critical (3) Received Response to Broadcast Maintenance Request, But no Unicast Maintenance opportunities received - T4 time out;CM-MAC=28:80:88:bc:0d:00;CMTS-MAC=00:c1:b1:61:06:3f;CM-QOS=1.1;CM-VER=3.0;
2019-9-10, 09:03:24 Critical (3) Unicast Ranging Received Abort Response - Re-initializing MAC;CM-MAC=28:80:88:bc:0d:00;CMTS-MAC=00:c1:b1:61:06:3f;CM-QOS=1.1;CM-VER=3.0;
2019-9-10, 09:04:28 Critical (3) Received Response to Broadcast Maintenance Request, But no Unicast Maintenance opportunities received - T4 time out;CM-MAC=28:80:88:bc:0d:00;CMTS-MAC=00:c1:b1:61:06:3f;CM-QOS=1.1;CM-VER=3.0;
2019-9-10, 10:16:05 Critical (3) Unicast Ranging Received Abort Response - Re-initializing MAC;CM-MAC=28:80:88:bc:0d:00;CMTS-MAC=00:c1:b1:61:06:3f;CM-QOS=1.1;CM-VER=3.0;
2019-9-10, 10:16:35 Critical (3) Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=28:80:88:bc:0d:00;CMTS-MAC=00:c1:b1:61:06:3f;CM-QOS=1.1;CM-VER=3.0;
2019-9-10, 10:16:37 Critical (3) Received Response to Broadcast Maintenance Request, But no Unicast Maintenance opportunities received - T4 time out;CM-MAC=28:80:88:bc:0d:00;CMTS-MAC=00:c1:b1:61:06:3f;CM-QOS=1.1;CM-VER=3.0;
2019-9-10, 11:20:06 Critical (3) No Ranging Response received - T3 time-out;CM-MAC=28:80:88:bc:0d:00;CMTS-MAC=00:c1:b1:61:06:3f;CM-QOS=1.1;CM-VER=3.0;
2019-9-10, 15:53:06 Critical (3) No Ranging Response received - T3 time-out;CM-MAC=28:80:88:bc:0d:00;CMTS-MAC=00:c1:b1:61:06:3f;CM-QOS=1.1;CM-VER=3.0;
2019-9-10, 16:17:17 Critical (3) No Ranging Response received - T3 time-out;CM-MAC=28:80:88:bc:0d:00;CMTS-MAC=00:c1:b1:61:06:3f;CM-QOS=1.1;CM-VER=3.0;
2019-9-10, 19:54:29 Critical (3) Unicast Ranging Received Abort Response - Re-initializing MAC;CM-MAC=28:80:88:bc:0d:00;CMTS-MAC=00:c1:b1:61:06:3f;CM-QOS=1.1;CM-VER=3.0;
2019-9-10, 19:55:01 Critical (3) Received Response to Broadcast Maintenance Request, But no Unicast Maintenance opportunities received - T4 time out;CM-MAC=28:80:88:bc:0d:00;CMTS-MAC=00:c1:b1:61:06:3f;CM-QOS=1.1;CM-VER=3.0;
2019-9-10, 19:56:06 Critical (3) Received Response to Broadcast Maintenance Request, But no Unicast Maintenance opportunities received - T4 time out;CM-MAC=28:80:88:bc:0d:00;CMTS-MAC=00:c1:b1:61:06:3f;CM-QOS=1.1;CM-VER=3.0;
2019-9-10, 21:58:51 Critical (3) No Ranging Response received - T3 time-out;CM-MAC=28:80:88:bc:0d:00;CMTS-MAC=00:c1:b1:61:06:3f;CM-QOS=1.1;CM-VER=3.0;
2019-9-10, 22:19:16 Critical (3) Unicast Ranging Received Abort Response - Re-initializing MAC;CM-MAC=28:80:88:bc:0d:00;CMTS-MAC=00:c1:b1:61:06:3f;CM-QOS=1.1;CM-VER=3.0;
2019-9-10, 22:19:21 Critical (3) Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=28:80:88:bc:0d:00;CMTS-MAC=00:c1:b1:61:06:3f;CM-QOS=1.1;CM-VER=3.0;
2019-9-10, 22:19:48 Critical (3) Received Response to Broadcast Maintenance Request, But no Unicast Maintenance opportunities received - T4 time out;CM-MAC=28:80:88:bc:0d:00;CMTS-MAC=00:c1:b1:61:06:3f;CM-QOS=1.1;CM-VER=3.0;
2019-9-10, 23:01:12 Critical (3) Unicast Ranging Received Abort Response - Re-initializing MAC;CM-MAC=28:80:88:bc:0d:00;CMTS-MAC=00:c1:b1:61:06:3f;CM-QOS=1.1;CM-VER=3.0;
2019-9-10, 23:01:44 Critical (3) Received Response to Broadcast Maintenance Request, But no Unicast Maintenance opportunities received - T4 time out;CM-MAC=28:80:88:bc:0d:00;CMTS-MAC=00:c1:b1:61:06:3f;CM-QOS=1.1;CM-VER=3.0;
2019-9-10, 23:02:48 Critical (3) Received Response to Broadcast Maintenance Request, But no Unicast Maintenance opportunities received - T4 time out;CM-MAC=28:80:88:bc:0d:00;CMTS-MAC=00:c1:b1:61:06:3f;CM-QOS=1.1;CM-VER=3.0;
2019-9-10, 23:34:29 Critical (3) Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=28:80:88:bc:0d:00;CMTS-MAC=00:c1:b1:61:06:3f;CM-QOS=1.1;CM-VER=3.0;
2019-9-10, 23:34:30 Critical (3) Unicast Ranging Received Abort Response - Re-initializing MAC;CM-MAC=28:80:88:bc:0d:00;CMTS-MAC=00:c1:b1:61:06:3f;CM-QOS=1.1;CM-VER=3.0;
2019-9-10, 23:35:02 Critical (3) Received Response to Broadcast Maintenance Request, But no Unicast Maintenance opportunities received - T4 time out;CM-MAC=28:80:88:bc:0d:00;CMTS-MAC=00:c1:b1:61:06:3f;CM-QOS=1.1;CM-VER=3.0;
2019-9-11, 06:17:31 Critical (3) No Ranging Response received - T3 time-out;CM-MAC=28:80:88:bc:0d:00;CMTS-MAC=00:c1:b1:61:06:3f;CM-QOS=1.1;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=28:80:88:bc:0d:00;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.0;CM-VER=3.0;
1970-1-1, 00:00:32 Notice (6) Honoring MDD; IP provisioning mode = IPv4
1970-1-1, 00:00:34 Warning (5) DHCP WARNING - Non-critical field invalid in response ;CM-MAC=28:80:88:bc:0d:00;CMTS-MAC=00:c1:b1:61:06:3f;CM-QOS=1.0;CM-VER=3.0;
2019-9-11, 06:53:11 Notice (6) TLV-11 - unrecognized OID;CM-MAC=28:80:88:bc:0d:00;CMTS-MAC=00:c1:b1:61:06:3f;CM-QOS=1.1;CM-VER=3.0;
2019-9-11, 06:53:18 Error (4) Improper Configuration File CVC Format
2019-9-11, 06:53:59 Critical (3) Received Response to Broadcast Maintenance Request, But no Unicast Maintenance opportunities received - T4 time out;CM-MAC=28:80:88:bc:0d:00;CMTS-MAC=00:c1:b1:61:06:3f;CM-QOS=1.1;CM-VER=3.0;
2019-9-11, 07:04:55 Critical (3) No Ranging Response received - T3 time-out;CM-MAC=28:80:88:bc:0d:00;CMTS-MAC=00:c1:b1:61:06:3f;CM-QOS=1.1;CM-VER=3.0;
Time Priority Description
1970-1-1, 00:01:06 Critical (3) SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=28:80:88:bc:0d:00;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.0;CM-VER=3.0;
1970-1-1, 00:01:12 Critical (3) No Ranging Response received - T3 time-out;CM-MAC=28:80:88:bc:0d:00;CMTS-MAC=00:c1:b1:61:06:3f;CM-QOS=1.0;CM-VER=3.0;
1970-1-1, 00:01:25 Critical (3) DHCP FAILED - Discover sent, no offer received;CM-MAC=28:80:88:bc:0d:00;CMTS-MAC=00:c1:b1:61:06:3f;CM-QOS=1.0;CM-VER=3.0;
1970-1-1, 00:00:20 Critical (3) SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=28:80:88:bc:0d:00;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.0;CM-VER=3.0;
1970-1-1, 00:00:23 Critical (3) SYNC Timing Synchronization failure - Failed to acquire FEC framing;CM-MAC=28:80:88:bc:0d:00;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.0;CM-VER=3.0;
1970-1-1, 00:00:25 Critical (3) SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=28:80:88:bc:0d:00;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.0;CM-VER=3.0;
1970-1-1, 00:00:44 Critical (3) SYNC Timing Synchronization failure - Failed to acquire FEC framing;CM-MAC=28:80:88:bc:0d:00;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.0;CM-VER=3.0;
1970-1-1, 00:01:01 Critical (3) No UCDs Received - Timeout;;CM-MAC=28:80:88:bc:0d:00;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.0;CM-VER=3.0;
1970-1-1, 00:01:02 Critical (3) SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=28:80:88:bc:0d:00;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.0;CM-VER=3.0;
1970-1-1, 00:01:10 Critical (3) No Ranging Response received - T3 time-out;CM-MAC=28:80:88:bc:0d:00;CMTS-MAC=00:c1:b1:61:06:3f;CM-QOS=1.0;CM-VER=3.0;
2019-9-10, 08:51:46 Critical (3) Received Response to Broadcast Maintenance Request, But no Unicast Maintenance opportunities received - T4 time out;CM-MAC=28:80:88:bc:0d:00;CMTS-MAC=00:c1:b1:61:06:3f;CM-QOS=1.1;CM-VER=3.0;
2019-9-10, 09:03:24 Critical (3) Unicast Ranging Received Abort Response - Re-initializing MAC;CM-MAC=28:80:88:bc:0d:00;CMTS-MAC=00:c1:b1:61:06:3f;CM-QOS=1.1;CM-VER=3.0;
2019-9-10, 09:04:28 Critical (3) Received Response to Broadcast Maintenance Request, But no Unicast Maintenance opportunities received - T4 time out;CM-MAC=28:80:88:bc:0d:00;CMTS-MAC=00:c1:b1:61:06:3f;CM-QOS=1.1;CM-VER=3.0;
2019-9-10, 10:16:05 Critical (3) Unicast Ranging Received Abort Response - Re-initializing MAC;CM-MAC=28:80:88:bc:0d:00;CMTS-MAC=00:c1:b1:61:06:3f;CM-QOS=1.1;CM-VER=3.0;
2019-9-10, 10:16:35 Critical (3) Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=28:80:88:bc:0d:00;CMTS-MAC=00:c1:b1:61:06:3f;CM-QOS=1.1;CM-VER=3.0;
2019-9-10, 10:16:37 Critical (3) Received Response to Broadcast Maintenance Request, But no Unicast Maintenance opportunities received - T4 time out;CM-MAC=28:80:88:bc:0d:00;CMTS-MAC=00:c1:b1:61:06:3f;CM-QOS=1.1;CM-VER=3.0;
2019-9-10, 11:20:06 Critical (3) No Ranging Response received - T3 time-out;CM-MAC=28:80:88:bc:0d:00;CMTS-MAC=00:c1:b1:61:06:3f;CM-QOS=1.1;CM-VER=3.0;
2019-9-10, 15:53:06 Critical (3) No Ranging Response received - T3 time-out;CM-MAC=28:80:88:bc:0d:00;CMTS-MAC=00:c1:b1:61:06:3f;CM-QOS=1.1;CM-VER=3.0;
2019-9-10, 16:17:17 Critical (3) No Ranging Response received - T3 time-out;CM-MAC=28:80:88:bc:0d:00;CMTS-MAC=00:c1:b1:61:06:3f;CM-QOS=1.1;CM-VER=3.0;
2019-9-10, 19:54:29 Critical (3) Unicast Ranging Received Abort Response - Re-initializing MAC;CM-MAC=28:80:88:bc:0d:00;CMTS-MAC=00:c1:b1:61:06:3f;CM-QOS=1.1;CM-VER=3.0;
2019-9-10, 19:55:01 Critical (3) Received Response to Broadcast Maintenance Request, But no Unicast Maintenance opportunities received - T4 time out;CM-MAC=28:80:88:bc:0d:00;CMTS-MAC=00:c1:b1:61:06:3f;CM-QOS=1.1;CM-VER=3.0;
2019-9-10, 19:56:06 Critical (3) Received Response to Broadcast Maintenance Request, But no Unicast Maintenance opportunities received - T4 time out;CM-MAC=28:80:88:bc:0d:00;CMTS-MAC=00:c1:b1:61:06:3f;CM-QOS=1.1;CM-VER=3.0;
2019-9-10, 21:58:51 Critical (3) No Ranging Response received - T3 time-out;CM-MAC=28:80:88:bc:0d:00;CMTS-MAC=00:c1:b1:61:06:3f;CM-QOS=1.1;CM-VER=3.0;
2019-9-10, 22:19:16 Critical (3) Unicast Ranging Received Abort Response - Re-initializing MAC;CM-MAC=28:80:88:bc:0d:00;CMTS-MAC=00:c1:b1:61:06:3f;CM-QOS=1.1;CM-VER=3.0;
2019-9-10, 22:19:21 Critical (3) Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=28:80:88:bc:0d:00;CMTS-MAC=00:c1:b1:61:06:3f;CM-QOS=1.1;CM-VER=3.0;
2019-9-10, 22:19:48 Critical (3) Received Response to Broadcast Maintenance Request, But no Unicast Maintenance opportunities received - T4 time out;CM-MAC=28:80:88:bc:0d:00;CMTS-MAC=00:c1:b1:61:06:3f;CM-QOS=1.1;CM-VER=3.0;
2019-9-10, 23:01:12 Critical (3) Unicast Ranging Received Abort Response - Re-initializing MAC;CM-MAC=28:80:88:bc:0d:00;CMTS-MAC=00:c1:b1:61:06:3f;CM-QOS=1.1;CM-VER=3.0;
2019-9-10, 23:01:44 Critical (3) Received Response to Broadcast Maintenance Request, But no Unicast Maintenance opportunities received - T4 time out;CM-MAC=28:80:88:bc:0d:00;CMTS-MAC=00:c1:b1:61:06:3f;CM-QOS=1.1;CM-VER=3.0;
2019-9-10, 23:02:48 Critical (3) Received Response to Broadcast Maintenance Request, But no Unicast Maintenance opportunities received - T4 time out;CM-MAC=28:80:88:bc:0d:00;CMTS-MAC=00:c1:b1:61:06:3f;CM-QOS=1.1;CM-VER=3.0;
2019-9-10, 23:34:29 Critical (3) Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=28:80:88:bc:0d:00;CMTS-MAC=00:c1:b1:61:06:3f;CM-QOS=1.1;CM-VER=3.0;
2019-9-10, 23:34:30 Critical (3) Unicast Ranging Received Abort Response - Re-initializing MAC;CM-MAC=28:80:88:bc:0d:00;CMTS-MAC=00:c1:b1:61:06:3f;CM-QOS=1.1;CM-VER=3.0;
2019-9-10, 23:35:02 Critical (3) Received Response to Broadcast Maintenance Request, But no Unicast Maintenance opportunities received - T4 time out;CM-MAC=28:80:88:bc:0d:00;CMTS-MAC=00:c1:b1:61:06:3f;CM-QOS=1.1;CM-VER=3.0;
2019-9-11, 06:17:31 Critical (3) No Ranging Response received - T3 time-out;CM-MAC=28:80:88:bc:0d:00;CMTS-MAC=00:c1:b1:61:06:3f;CM-QOS=1.1;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=28:80:88:bc:0d:00;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.0;CM-VER=3.0;
1970-1-1, 00:00:32 Notice (6) Honoring MDD; IP provisioning mode = IPv4
1970-1-1, 00:00:34 Warning (5) DHCP WARNING - Non-critical field invalid in response ;CM-MAC=28:80:88:bc:0d:00;CMTS-MAC=00:c1:b1:61:06:3f;CM-QOS=1.0;CM-VER=3.0;
2019-9-11, 06:53:11 Notice (6) TLV-11 - unrecognized OID;CM-MAC=28:80:88:bc:0d:00;CMTS-MAC=00:c1:b1:61:06:3f;CM-QOS=1.1;CM-VER=3.0;
2019-9-11, 06:53:18 Error (4) Improper Configuration File CVC Format
2019-9-11, 06:53:59 Critical (3) Received Response to Broadcast Maintenance Request, But no Unicast Maintenance opportunities received - T4 time out;CM-MAC=28:80:88:bc:0d:00;CMTS-MAC=00:c1:b1:61:06:3f;CM-QOS=1.1;CM-VER=3.0;
2019-9-11, 07:04:55 Critical (3) No Ranging Response received - T3 time-out;CM-MAC=28:80:88:bc:0d:00;CMTS-MAC=00:c1:b1:61:06:3f;CM-QOS=1.1;CM-VER=3.0;
8 Replies
Can you get a screen snip of your connectins page that includes both downstream and upstream power levels and info?
A lot of your errors tend to be signal errors. That screen snip can help out a lot.
A couple things you can do to try to help with it.
1. remove splitters from the lines
2. remove any 90 degree elbows from line
3. remove any amplifiers from the line
4. Try to connect the modem directly where the line comes into the house and test from there.
5. Inspect your cables. water damage to a cable or even water within a cable can cause errors. check for cheap connections, damaged cables, bent (kinked) cables. Replace these.
- The modem is in the basement of a 3 story town house and it is hooked to the line that comes from directly outside. There are no splitters or amplifiers in there. Here is a screenshot of the down and up
What ISP are you using?
the cm500 is a 16x4 modem. Not sure if this is true for all isp's firmware but in my experience if there isn't all the channels to lock for the modem, they still show but not as locked. Yours is only showing as a 8x3?
