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Forum Discussion
CM500-100NAS Questions
Hi. Modem just hit 93 days. It's gone down twice recently. Any suggestions on how to troubleshoot? Comcast/Xfinity support is terrible (and there are no other high speed choices in my area). My second question is: Has anyone ever found a way to export these logs? They could be helpful.
Hardware Version C312T00-01
Firmware Version V1.01.14
Thank you,
JB
| Time | Priority | Description |
| 2020-12-1, 15:52:27 | Notice (6) | Honoring MDD; IP provisioning mode = IPv6 |
| 2020-12-1, 15:52:18 | Critical (3) | Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=44:a5:6e:cc:a8:78;CMTS-MAC=00:01:5c:69:86:75;CM-QOS=1.0;CM-VER=3.0; |
| 2020-12-1, 15:51:15 | Critical (3) | No Ranging Response received - T3 time-out;CM-MAC=44:a5:6e:cc:a8:78;CMTS-MAC=00:01:5c:69:86:75;CM-QOS=1.0;CM-VER=3.0; |
| 2020-12-1, 15:49:37 | Critical (3) | Received Response to Broadcast Maintenance Request, But no Unicast Maintenance opportunities received - T4 time out;CM-MAC=44:a5:6e:cc:a8:78;CMTS-MAC=00:01:5c:69:86:75;CM-QOS=1.1;CM-VER=3.0; |
| 2020-12-1, 15:49:01 | Critical (3) | SYNC Timing Synchronization failure - Failed to acquire FEC framing;CM-MAC=44:a5:6e:cc:a8:78;CMTS-MAC=00:01:5c:69:86:75;CM-QOS=1.1;CM-VER=3.0; |
| 2020-12-1, 15:47:18 | Critical (3) | SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=44:a5:6e:cc:a8:78;CMTS-MAC=00:01:5c:69:86:75;CM-QOS=1.1;CM-VER=3.0; |
| 2020-12-1, 15:47:16 | Warning (5) | MDD message timeout;CM-MAC=44:a5:6e:cc:a8:78;CMTS-MAC=00:01:5c:69:86:75;CM-QOS=1.1;CM-VER=3.0; |
| 2020-12-1, 15:47:14 | Critical (3) | SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=44:a5:6e:cc:a8:78;CMTS-MAC=00:01:5c:69:86:75;CM-QOS=1.1;CM-VER=3.0; |
| 2020-12-1, 15:47:10 | Warning (5) | MDD message timeout;CM-MAC=44:a5:6e:cc:a8:78;CMTS-MAC=00:01:5c:69:86:75;CM-QOS=1.1;CM-VER=3.0; |
| 2020-11-16, 03:02:32 | Notice (6) | Honoring MDD; IP provisioning mode = IPv6 |
| 2020-11-16, 03:02:07 | Critical (3) | No Ranging Response received - T3 time-out;CM-MAC=44:a5:6e:cc:a8:78;CMTS-MAC=00:01:5c:69:86:75;CM-QOS=1.0;CM-VER=3.0; |
| 2020-11-16, 03:02:02 | Critical (3) | SYNC Timing Synchronization failure - Failed to acquire FEC framing;CM-MAC=44:a5:6e:cc:a8:78;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.0;CM-VER=3.0; |
| 2020-11-16, 03:01:40 | Critical (3) | SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=44:a5:6e:cc:a8:78;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.0;CM-VER=3.0; |
5 Replies
Have the ISP check the signal and line quality UP to the modem. Be sure the ISP provisions the modem correctly.
Be sure there are no coax cable line splitters in the between the modem and ISP service box.
Be sure your using good quality RG6 coax cable up to the modem.
Be sure to power OFF the modem for 1 minute them back ON.
https://community.netgear.com/t5/Cable-Modems-Routers/General-info-and-Troubleshooting-for-Cable-Modems/m-p/1530376#M12853A screen snip is usually the easiest to read. attach it to the post.
do you also have a screen snip of the cable connections page?
Attaching cable connections log
Attaching snip of logs
You're caught in a catch-22. The signals strenghts/errors don't look to bad and when the logs do indicate issues, its only every couple weeks. If it truly is only every couple weeks its going to be tough for the ISP to say, yes its the line when its so infrequent.
And its tough to test changes because it does happen so infrequent. I normally tell people to direct connect a pc to the modem (to rule out router issues) and run it but from the looks of it, its rarely happening and you couldn't have 1 device connected for that long to test.
I'm not sure what a good plan for you is.
you can have the isp check it but not sure if they'll find much.
You could try a different modem. A docsis 3.1 modem might be a bit more tolerant but again, tough to say.
