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Modem reading, sanity check

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Modem reading, sanity check

Hello. I just want a sanity check on these reading. I'm getting the speeds I'm paying for 250d/10u, but occasionally the network just stops for 30-60 seconds. Comcast says my modem is within spec, but the Xfinity online status center shows "Issue Detected". Tier 1 and Tier 2 support cannot figure out why it says issue detected (yes, they rebooted and did their troubleshooting).

 

I think this all looks good, with the possible exception of upstream power, but this is really outside my wheelhouse (I'm a database guy). Thanks in advance.

 

I also notice that the system time at the bottom of the Cable Connection page is off by 1 hour. 

 

About my modem: https://cdn.head-fi.org/g/9940028_l.jpg

Status Center error message: https://cdn.head-fi.org/g/9940029_l.jpg

Start up: https://cdn.head-fi.org/g/9940030_l.jpg

Downstream: https://cdn.head-fi.org/g/9940027_l.jpg

Upstream: https://cdn.head-fi.org/g/9940031_l.jpg

 

 

 

 

 

 

Frequent Visitor

Re: Modem reading, sanity check

Sorry, I cannot figure out how to post images. Grr.

Expert

Re: Modem reading, sanity check

Don't see any "readings" posted... ? And modems don't change between standard and daylight savings time, so that's normal.



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Expert

Re: Modem reading, sanity check


@AllanMarcus wrote:

Sorry, I cannot figure out how to post images. Grr.


Try hosting them at one of those free third-party pic hosting sites and post the link to them here.



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Expert

Re: Modem reading, sanity check

The pic that you posted doesn't show the signal stat figures.

 



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Re: Modem reading, sanity check

I just posted the links. If I try to use the "Insert Image" option, and paste in the link, the comcast site says I'm using illegal HTML. Grr.

Expert

Re: Modem reading, sanity check

O/k the downstream power is a tad high but not critical. 



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Re: Modem reading, sanity check

occasionally there are 30-60 second delays when using the net. Usually when just starting to use a device. Might be the router, but I wanted to eliminate the modem first. Also, the "issue dedected" from the status center is diconcerting. 

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Contributor

Re: Modem reading, sanity check

I believe the issue detected is due to you using a non comcast supplied  modem(CM1000). The service center does not have complete access to your modem. My status also shows that message.

 

Had similar problems with occasional slowdowns  until I reset my router to factory defaults.  No issues since, I am also using a docsis 3.1 modem (MB8600)on a non-gigabit service.  

Expert

Re: Modem reading, sanity check

@AllanMarcus wrote:

Also, the "issue dedected" from the status center is diconcerting. 



@jw32097 wrote:

I believe the issue detected is due to you using a non comcast supplied  modem(CM1000). The service center does not have complete access to your modem. My status also shows that message.

That's correct. If one is using a retail device rather than one that is rented from them, the system gets confused and that message gets displayed.



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Expert

Re: Modem reading, sanity check


@AllanMarcus wrote:

occasionally there are 30-60 second delays when using the net. Usually when just starting to use a device. Might be the router, but I wanted to eliminate the modem first.


Is this with a WiFi connection ? If so, for a test, does a computer hardwired directly to the router with an ethernet cable have the same problem ?



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Re: Modem reading, sanity check

thanks for the info. I'm pretty sure the delay issue is relacted to the WiFi, not the modem.

 

If I perform a factory reset on the modem, will it just reset, reboot, and they start workign, or do I need to Comcast for reprovisioning?

Expert

Re: Modem reading, sanity check

Yes it will. The provisioning is not lost.



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CM1000 needs modem reset every 3-5 days

I have a CM1000 modem. I've posted the signal readings here:

 

https://forums.xfinity.com/t5/Your-Home-Network/Modem-reading-sanity-check/td-p/3209175

 

And all the readings appears to check out as OK. My issue is that every 3-5 days we lose internet connectivity. The ASUS router reports that the modem is not providing DHCP services. If I manually reboot the modem by powering it off and on, the issue is not resolved. The ASUS router will still report no DHCP service from the modem. If I logon to my Xfinity account (via cellualr) and restart the modem from there, after the modem restarts the ASUS router connects back up just fine.

 

This sort tells me something in the modem is getting lost, and a reboot from Xfinity might be reprovisioning the config file, or something. While I'm and IT guy, this is outside my area of expertise.

 

Any ideas why the modem fails after a few days, why a cold restart doesn't work, but a remote restart from Xfinity works? Anything I can do to troubleshoot? 

Expert

Re: CM1000 needs modem reset every 3-5 days

FWIW, a modem reloads a boot file / config file each and every time that it is power cycled / rebooted whether that is done remotely or manually at the device itself.

What it the WAN lease length / time period indicated in the router's "Internet Status" dialog ? When it occurs, are the WAN IP address and / or the DNS servers lost ?


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Re: CM1000 needs modem reset every 3-5 days

I'm using ASUS_Merlin, and I cannot find the WAN lease length anywhere on the GUI or the CLI.

 

When I lose connectivity, the router reports: Your ISP's DHCP does not function correctly

Frequent Visitor

Re: CM1000 needs modem reset every 3-5 days

re: FWIW, a modem reloads a boot file / config file each and every time that it is power cycled / rebooted whether that is done remotely or manually at the device itself.

 

Sure, that makes sense, but when I manuall restart the modem (power it off, wait a minute, power it on), the router does not ever discover the modem's DHCP. When I restart it via the Xfinity web site, the ruter does see it. Something is different.

Frequent Visitor

Re: CM1000 needs modem reset every 3-5 days

Umm, the issue just happened again. I'm begining to this this is a router issue. When I turned off the WAN on the router, then turn it back on, it got a DHCP lease. I will post on the merlin forum. 

 

IT sure is complicted :-)

Expert

Re: CM1000 needs modem reset every 3-5 days


@AllanMarcus wrote:

.I will post on the merlin forum. 

 

Good idea. I don't know much about the 3rd party Merlin firmware, sorry. Please post back with any answers !

 

IT sure is complicted :-)

 

Yep ! It sure can be.


 



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