For the past couple of years, I've been delegated a /59 subnet with a prefix ending in f0e0. If I requested more prefixes, I would get the next each in the sequence f0c0, f0a0, f080, f060, and then f040. I've never been delegated a prefix ending in f020, even when I tried in testing. My notes on that, I posted here: http://setupnotes.gozoinks.com/comcast-IPv6-prefix-exhaustion
A few weeks ago, toward the end of February I think but I'm not sure, my prefix changed to one ending in f020, and IPv6 no longer works.
I would love to know what has changed between last July, when I couldn't get an f020 prefix if I tried, and today, when f020 is all I can get. Failing that, I'd love some insight that might help me understand how to fix my IPv6.
This is an interesting issue! I'd be really glad to dig into this and see if I can get some answers for you with the prefix delegation and IPv6. Please click on my handle (Comcast_Gina) and send a private message with your name, the business name, the complete service address (including city, state, ZIP, suite number, etc), and the phone or account number, and any/all the pertinent details so we can help!
Since my first post, I blocked releasing my DHCP lease in dhcp6c, and then I changed my firewall's DUID. Now I've been delegated a prefix ending in f040, which suggests the modem is now delegating prefixes in ascending order instead of descending order, which is interesting; however, the modem still does not seem to be routing data from the *:f040 subnet.
I will PM you details.
Thanks for taking the time to reach out to us through the business forums. I am very sorry for the delay in our response. I would love to get to the bottom of the connection issues as I realize how important this service is to your business. Can you please reach out through private message with your first and last name, full service address and account number or phone number?