Visitor

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2 Messages

Monday, August 4th, 2025

Arris rejecting CM Config for invalid TLV-4

A new DOCSIS 3.1 Arris G36 is unable to activate after it receives, but finds invalid content in xFinity's CM Config file.  The logged error identifies TLV-4, but not a specific sub-value.

TLV-4 contains 'Class of Service', which appears (in DOCSIS 3.1 materials I have found) to be:

         ClassID;                             /* TLV: [4.1]*/
         MaxDownstreamRate;      /* TLV: [4.2]*/
         MaxUpstreamRate;        /* TLV: [4.3]*/
         UpstreamChannelPriority;/* TLV: [4.4]*/
         MinUpstreamRate;        /* TLV: [4.5]*/
         MaxUpstreamBurst;       /* TLV: [4.6]*/
         CoSPrivacyEnable;       /* TLV: [4.7]*/

Is there a fairly recent (late 2024, early 2025) DOCSIS change to the CM config file implemented by xFinity but not [yet] part of Arris' firmware?

Is it possible there are different config files for xFinity-provided gateways than for off-the-shelf Arris G36, and why wouldn't first-level-support know about this?

Anyone offer any suggestions? I have no internet until a path forward is identified for this xFinity-supported device.  It appears the only two solutions are xFinity 'fix' the config file it sends to me or xFinity pushes a Arris firmware update to my device.

Thanks!

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Visitor

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2 Messages

21 days ago

Resolved with my apologies for stirring the pot.  Comedy of errors.  Glossy xfinity literature distributed by apartment complex leads tenants to believe service is already enabled at this facility and that activation is as simple as using the app to associate the line, CM-MAC, and xfinity account.      *FALSE*       - the [xfinity] cable coming into this apartment was not physically connected at the Comcast pedestal.   BUT, and here's the fun part: one of the coax outlets in the apartment had good signal, and that is the one I had my modem connected to, but this outlet is ... a Service Electric outlet.  So, the latter provider isn't sending legitimate config, but I don't care.

Plugged into an actual live xFinity outlet and the modem seemed to start first try as one would hope.   The tech did do 'provision' the modem (whatever that means) after the first successful boot, and he caused the modem to restart, but all my modem settings, WiFi SSIDs, admin password, et. al. seem to be how I had them set before he arrived.  I was afraid he'd do a factory reset or force some firmware, or something, but seemingly nothing along those lines.

In these early minutes, the Arris G36 seems to be working fine.  Too soon to tell if the performance is as expected.

Official Employee

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951 Messages

Happy to hear everything went well with the service appointment. @user_sq5hqr If you need anything in the future, we are only a post away

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Official Employee

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440 Messages

23 days ago

Hey there user_sq5hqr. I would be happy to pull up your account and take a look into this for you.

Please send us a direct chat message with your full name and complete service address to “Xfinity Support”. To do so, click on the chat icon located at the top right of this forums page.

 

To send a "Direct Message" to Xfinity Support:

 

Click "Sign In" if necessary

Click the "Direct Messaging" icon or  https://forums.xfinity.com/direct-messaging

Click the "New message" (pencil and paper) icon
The "To:" line prompts you to "Type the name of a person". Instead, type "Xfinity Support" there

As you are typing a drop-down list appears. Select "Xfinity Support" from that list

An "Xfinity Support" graphic replaces the "To:" line

Type your message in the text area near the bottom of the window and press Enter to send it.

 

Expert

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112.9K Messages

23 days ago

@user_sq5hqr @XfinityJon 

Please circle back here and post any possible solutions for the issue here in these open public forums so that all readers here may benefit from the exchange / info. This is in keeping with the spirit for which these public help forums were originally intended. Thank you.

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