ipv6 address assignment via local server from isp assigned block

I have been looking around and found the information confusing as best. Is there a way to have a server "recieve" the /64 ipv6 block from the isp and then use dhcp or something to assign it out to the local machines so that

1) dns entries are correct for ipv6 addresses? Im sure a script needs to be written so that the external dns host for the domain can be updated as the ns for the local domain shifts around.

2) internal machines can be assigned addresses in a logical manner as well as management from a server can be done. I understand that the addresses will/can change due to isp. I am trying to find a way for those dynamic addresses to be managed/assigned in a straightforward manner

I am running a freeipa server in centos 7 that I hope to be able to have the dns properly updated from/through. but if there is a better tool out there that I can find a way to integrate in to freeipa that would work as well.