I recently upgraded my contract that included a new modem. The entire experience end-to-end has been a nightmare. The purpose of this post is to, along with many others, to let anyone else know thinking of voluntarily upgrading their bandwith and contract to support it, not to if you have IPV6 PD deleegation working and using IPV6 to access the public network and need it. Need it or not, its supposed to work. It doesnt and its Comcast's issue.
I've have IPV6 PD working behind my old Netgear gateway since January 2014 until 6/9 when a service appointment upgraded my gateway to a DPC3939B. As I said the entire process here has been a nighmare. Starting with the technician onsite at my location all the way through my most recent call to support yesterday.
I mention the DPC3939B but it doesnt seem to matter. From other posts, it seems all Comcast's business gatesays have this issue. Initially, the 3939B would not even respond to a ICMPV6 router solicitation or send ICMPV6 router advertisements. Following the advice of one knowledgable CSR, I performed a factory reset. This seemed to correct the ICMPV6 RA issue but traffic still would not route. The next call to support ordered the DPC3939B be replaced with a CBR.
The onsite tech would not replace my DPC3939B with a CBR citing my bandwidith was below 500Mbs. He replaced it with what he said was a Technicolor. The fact was he replaced it with another Cisco unit, DPC3941B. But as I said, any Comcast Business Gateway used as a replacement wouldnt matter. U
Hi there, thanks so much for taking the time to reach out to the Digital Care Team here through the forums. I am so sorry to see that you are having an issue with your routing once upgrading, I know how frustrating this can be and you have reached the right team to help make sure we get this taken care of. Can you please send us a private message with your name, the full address, and the phone or account number?
I don't have any experience with the DPC3939B but I have been able to get IPv6 working on the DPC3941B (BWG). However, I did have to request some help through these forums to get it working again recently. Support had to roll back my BWG firmware to 'dpc3941b-v303r20421771-190327a-CMCST' in order to restore PD. You can check this by browsing to Gateway > Software on the modem to see what version you have. If you have a recent verion from this year you will not be able to get PD, it seems to have a bug. I didn't have any luck getting PD to work on the CBR-T... it would delegate but no communications would occur. I believe the the modems are failing to route the traffic to the router they are assigning the prefix to. Last time I talked to support they said the issue with the CBR-T has not been resolved.
i thought the same thing regarding firmware. I only hoped Comcast would roll forward with a fix versus having to roll back. I opened yet another case with Comcast to roll back the firmware and also PM’d Comcast_Anisa. Hopefully somewhere between either of these channels I’ll get this fixed.
BTW my firmware is
Hi Axworth, I just replied to your private message and think that these links may be helpful so I am providing them here in the public thread for you and the rest of the community as well:
If you have more information or questions, feel free to respond to the private message. We'll be standing by.
I am sorry this link was not helpful. I will be happy to follow up on your request and we may need to work with our advanced repair team further. Are you able to send a private message with your name, service address, and account number so I can assist as thoroughly as possible?
Comcast team, I just got a DPC3941B installed as well, and Prefix Delegation is totally broken, the modem thinks the delegated prefix is on the same link vs. properly routing it to the PD router.
Can I get my modem's firmware rolled back to dpc3941b-v303r20421771-190327a-CMCST as mentioned by someone else in this post? It's currently DPC3941B_3.9p17s1_PROD_sey and obviously bad.
Hello, how are you? I hope overall your day has been a good one! I am sorry you are experiencing issues with the new modem and Prefix Delegation. I know this issue is hindering your ability to manage your network. We typically can't rollback firmware, but I can make sure your modem is online, updated, and your connection is working properly. Are you able to send a private message at your convenience? Capturing your name, service address, and account number (or phone number) will help me work on this for you.
I am so sorry to hear that this did not address your IPV6 routing concerns. I would love to dig further into the service issues if you could please reach out through private message with the requested account information I would be happy to get started.