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System log and modem both going nuts

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New Around Here
Running RMerlin 386.7_2 on RT AX86U. My log is going crazy and so is my modem. Log file attached. I really hope someone is willing to take the time to have a look. I've spent 3 days now on the log and perusing old forum posts. The problems began maybe a month ago, and I upgraded the firmware as part of troubleshooting.

Here are the highlights.

The wi-fi random key is resetting every few seconds. For most of the day/night, the log shows constant key changes and devices disassociating and re-associating, or failing to authenticate because the key changes so quickly.

For most of the log, I had key rotation set to 7200 for 5GHz and 3600 for 2.4GHz. I changed both to zero around 18:00 or 19:00 the evening of Oct. 29.

Multiple times a day, internet calls from various devices will break the internet. Usually, the modem will reboot with the following log entries each time:
TLV-11 - unrecognized OID;CM-MAC=20:3d:66:09:c6:74;CMTS-MAC=00:01:5c:74:2e:c0;CM-QOS=1.1;CM-VER=3.0;
Oct 29 2022 14:51:20
MIMO Event MIMO: Stored MIMO=-1 post cfg file MIMO=-1;CM-MAC=20:3d:66:09:c6:74;CMTS-MAC=00:01:5c:74:2e:c0;CM-QOS=1.1;CM-VER=3.0;
Jan 01 1970 00:00:23
No Ranging Response received - T3 time-out;CM-MAC=20:3d:66:09:c6:74;CMTS-MAC=00:01:5c:74:2e:c0;CM-QOS=1.1;CM-VER=3.0;
Jan 01 1970 00:00:17
Cable Modem Reboot due to T4 timeout ;CM-MAC=20:3d:66:09:c6:74;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.1;CM-VER=3.0;
Oct 29 2022 14:50:30
Received Response to Broadcast Maintenance Request, But no Unicast Maintenance opportunities received - T4 time out;CM-MAC=20:3d:66:09:c6:74;CMTS-MAC=00:01:5c:74:2e:c0;CM-QOS=1.1;CM-VER=3.0;
Oct 29 2022 14:50:00
No Ranging Response received - T3 time-out;CM-MAC=20:3d:66:09:c6:74;CMTS-MAC=00:01:5c:74:2e:c0;CM-QOS=1.1;CM-VER=3.0;``

I think the router traffic kills the modem, rather than the other way around, for two reasons: (a) the internet will stay down indefinitely until I reboot the router, at which point it reconnects (for a few hours or half a day); (b) I will be streaming radio through chromecasts for hours, then open a browser window on my laptop or ask Siri a question, and the internet immediately goes out, as indicated by the radio streaming.

The cycle of the wan going down usually starts with this line (at least, where I identify it):
`Oct 29 10:37:25 kernel: CPU: 1 PID: 695 Comm: dcd Tainted: P O 4.1.52 #2
kernel: Hardware name: Broadcom-v8A (DT)`

It involves this error:
`wsdd2[25335]: error: wsdd-mcast-v4: wsd_send_soap_msg: send`

And it will lose ethernet, wan, immediately reconnect ethernet, and then struggle to get the wan connection back up.
''Oct 29 13:50:36 kernel: eth0 (Int switch port: 3) (Logical Port: 3) (phyId: c) Link DOWN.
Oct 29 13:50:43 WAN_Connection: WAN(0) link down.``

Occasionally the sequence that includes these lines corresponds to a modem reboot, but at other times not. For example, I've seen my Google home devices suddenly unable to connect, but no modem reboot and in fact no sign of wan_connection down.

I've turned off diversion, disabled AICloud and UPNP, and a few other things (including key rotation, as noted). Trying to understand it and avoid a 30/30/30 reset, since that would force me to relearn some things in order to set up the router again. Here's hoping someone can generously shed some light.


  • syslog (4).txt
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Tech Junky

Very Senior Member
T3/4 timeouts indicate an ISP issue whether a splitter or connector went bad or if it's an outside line issue. Call the ISP and report it so they can take a look.

The router on the other hand I would revert to stock firmware to see of it's the fw or a hw issue and go from there. A router won't cause your CM to stall or reboot.


Part of the Furniture
30 30 30 reset does not work for Asus. That is an old Linksys procedure.
Going to Asus 388 code firmware is a good recommendation. And, do not mess with the default WIFI settings! Most of the routers sold are set up once by consumers who know nothing about networking and the router works!


Part of the Furniture
If you are getting many T3, T4 timeouts, this suggests poor signal quality coming in from the cable modem head end...

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