So, after 24 hours of playing with Comcast's "native" IPv6 this weekend, the kludges of Comcast's DHCPv6 implementation is apparent.

Anyway, Comcast's implementation wasn't really respecting the promised lifetime of the prefix it was handing out. If my cable modem reset for any reason, ie a T4 timeout (which is a more than daily thing), it appeared the lease will be silently cancelled by the CMTS (Cable Modem Termination System) and the DHCPv6 client (an Airport Extreme) will be none the wiser and the IPV6 connection will be dead-dead. Looking into this on Comcast's KB and forums and other places, there are tons of complaints and bug reports out there about Comcast's IPV6 prefix delegations failing to renew when it naturally expires or whenever the modem resets causing IPV6 to drop.

I'm sure there is a "good" reason they are using busted set of patches and implementing IPv6 this way. They also rolled my CMTS back, it was just bad. As of Mid-Sunday... no more "native" IPv6 for me.

Someday.