IPv6 network and routing

[stanthewizzard]

Hello

I have a functionnal ipv6 network

My ISP delegate 2a01:cb00:xxxx:xxxx::/64
Opnsense DHCP distribute ip with 2a01:cb00:xxxx:xxxx::

Everything is fine and runing.

But sometime my ISP changes the delegation. Not a good thing with server.

Could I use ULA for certains servers (Active Directory and Pi-Hole for exemple) and route 2a01:cb00:xxxx:xxxx:: to this ULA ?
How could I have fixed ipv6 in the lan whatever the prefix is ?

Thanks for help (I'm lost TBH)

[dseven]

You could use a ULA prefix for your LAN and NPTv6 to map it (dynamically) to your delegated prefix.

[stanthewizzard]

Thanks :)

So in NPTv6
   2a01:cb00:xxxx:yyyy::/64   fd2a:ef:f0:73:xxxx::/64   None

from 2a01:cb00:xxxx:yyyy::11 ping fd2a:ef:f0:73:xxxx::53
request timed out

Not working