I suffered internet disconnection caused by cable modem reboot or malfunction. It happened every few hour or feww days. I tried contact technical service and on-site check. They all failed to find the root cause. I will post cable model log and hope there is a solution without switching modem. Thanks.
1. Sepctrum internet.
2. Motorola MB7420
3. ASUS AC 1300
Cable modem log
2. Event log
Usually reboot cable modem and router will fix the connectivity but only last a couple of hours or days.
Here is the router log.
Jul 22 21:26:53 rc_service: ntp 837:notify_rc restart_diskmon
Jul 22 21:26:53 disk_monitor: Finish
Jul 22 21:26:55 disk monitor: be idle
Jul 22 21:27:01 crond: time disparity of 1565126 minutes detected
When you try to "reboot", you have to start the modem first and wait until all the LED indicators stop flashing, THEN apply power to the router and let it boot up. You might also need to reset your router to factory defaults if it does not receive the proper network setup values from the modem.
Thanks for the reply.
Yes, that's indeed the procedure I used to reboot everyting. Here is the detailed steps
1. Turn off cable modem and router.
2. Turn on cable modem until the globe icon stop flashing and turn to solid green light.
3. Turn on router and wait for connections to be estabilished.
But such procedure does not guarantee a reliable connection.
Another thing I tried is to reset and restore the factory default setting for both the cable modem and router. But this fails to solve the probem as well.
The lastest thing I tried is to set traffice manger QoS (upload: 3Mb/s Download: 80 Mb/s) This seems to have a better connection but still fails after a few hour today. Also, this method seems stupid to me.
Any comment or suggestions?
Have you checked all the coax connections from the point the cable comes in from the street to the modem for any loose connections or damaged coax?
I personally check the connection from wall plug to cable modem and the connection in the in the electrical room. Both seems to have tight coax cable connection.
And there was a spectrum technician check all the cable signal and found no issues.
Is there any other info I can provide to help debug? Thanks
First, turn off those traffic manager functions in your router for now. When your data flow approaches the limits you set for upload and download speeds they add extra delays, which really screws up the Speedtest results.
Next, as @RAIST5150 said, disconnect any in-house cable that doesn't have a device or terminator attached. If your existing splitter has any open, unused ports, those too MUST have terminations installed to keep the noise out!
What we can see of your signal levels look OK, but the SNR (Signal to Noise ratio} is below 40 on every channel. We REALLY need to see the corrected and uncorrected data packet errors. Those get reset to zero when you unplug power to the modem. Let the modem run for at least six hours (preferably more than 12) and then copy and post the signal page here. That will give us some valuable information about your home connection.
1. I disable the traffice manager function in the router.
2. Install terminator for all the unconnected plugs.
Right after the reboot.
After two weeks and a few calls with spectrum service. My internet is more stable now to show log more than two days. And here is the log
Signal levels of both the downstream [DS] and upstream [US} channels are very good. It looks like Spectrum has masked the packet errror counters since both the corrected and uncorrectable error counts are still displaying all zeros after almost 72 hours. That simply NEVER happens, there are always errors detected while the modem auto-ranging circuits adjust the signal levels between all of the video channnels.