jntc's profile

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18 Messages

Monday, April 26th, 2021 8:24 PM

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Cannot access modem diag screen

Just got a new MB8611 (my own) and prior to configuration change (speed increase thru comcast) I was able to see modem diagnostics (which I monitor for SNR and strength) via 192.168.100.1

I now see these ports are filtered by the modem, and I am no longer able to monitor.

Why does comcast lock me out of my own modem now?

Can this be re-enabled?

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26.3K Messages

4 years ago

If you are not renting one of Comcast's gateways, I don't think they can block http://192.168.100.1.

What happens exactly when you try to access the modem's signal pages?

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18 Messages

port is being filtered, so no connection:

Starting Nmap 7.60 ( https://nmap.org ) at 2021-04-26 17:04 EDT
Nmap scan report for 192.168.100.1
Host is up (0.0025s latency).
Not shown: 998 closed ports
PORT    STATE    SERVICE
80/tcp  filtered http
443/tcp filtered https

Contributor

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18 Messages

4 years ago

Modem is my own. 

Port scan shows 80 and 443 active but filtered.  A UDP scan shows 161 (SNMP) open, but it is not accessible via snmpwalk (and public community string).

Rebooting the modem allows web access (via port 80) until modem pulls config, then I'm locked out again.

(And yes, it's activated)

(edited)

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18 Messages

Any ideas on how I can go about getting this corrected?  Seems I should have access to my own modem for diag purposes...

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18 Messages

4 years ago

@ComcastAdrienne @ComcastMorgan @ComcastAbbie @ComcastThomasF 

Comcast, your tech support folks have no idea what I'm talking about when I call about this.  Can you help?

I'm being told that I 'should' have access to my side of the modem diag/login page - especially with it being my own and not rented.

Thank you for the anticipated response!

Gold Problem Solver

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26.3K Messages

4 years ago

Are you able to access the signal pages by connecting your computer directly to the modem's Ethernet port? If so your router may be interfering and https://motorolamentor.zendesk.com/hc/en-us/articles/360004337933-MB8600-Not-able-to-login-to-modem-on-the-network- may help. Other posts here in the Forums seem to suggest that customers are using the MB8611 without this problem.

If the signal pages are not available even with a direct connection then Comcast is likely blocking them. I don't know why they would and I've not seen this with http on 192.168.100.1, but I have seen SNMP behave exactly as you describe. Before Comcast took over my local cable system I could use SNMP to check modem info. As soon as they took it over, SNMP only worked at power up and went dead as soon as the modem finished its startup sequence and went online.

If they're blocking the pages the simplest fix might be to return the modem and replace it with a different model. The chances of finding someone who understands the problem is close to zero, and chances of finding someone who can fix it are even closer to zero.

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18 Messages

4 years ago

@ComcastJosephB @ComcastJoey 

- are you able to assist by any chance?

(edited)

Gold Problem Solver

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7.2K Messages

Hello J Nash, the information that BruceW shared is correct. We cannot block any ports for equipment that's not ours, if your port is being filtered we should try a factory reset of the modem to correct this problem. Please refer to your owners manual for instructions on how to perform the reset. 

I no longer work for Comcast.

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18 Messages

@ComcastAmir 

If I reset, I can access with no problems, but once I get a lock and the config file TFTPs in and establishes internet, the ports are again filtered.

If I reset and leave the coax unhooked, I can access with no problems as well.  

Gold Problem Solver

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26.3K Messages

4 years ago

@ComcastAmir wrote: ... We cannot block any ports for equipment that's not ours ...

That's not quite correct, according to https://www.xfinity.com/support/articles/list-of-blocked-ports

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1 Message

4 years ago

I have this issue right now. Brand new modem. Could connect to modem through 192.168.100.1 before activating. Once activated with xfinity, I can no longer access.a

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671 Messages

Hey @user_3c0328 we haven't heard back from the original poster as of yet, so I can't be sure if the issue was resolved, but we're happy to help. Can you confirm the modem model number you're using, and if you're getting an 'ACCESS DENIED' style error when trying to access that 192.168.100.1? 

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