I have to change the configured IPv6 address of my hosting server. Until recently, Online was offering a very simple IPv6 mode (SLAAC, I think). They decided to change the IPv6 schema (from 20a1:: to 2001::), and make mandatory for all customers to reserve an IPv6 / 48 bloc (even if most clearly don't need it). Of course, without any delay, ant not even an email announcement.

First I think this is scandaleous and a huge and unacceptable lack of professionalism.

IRC support chanel is a long procession a customers having "lost" their IPv6...

More, no correct documentation available (I will not use dibbler when dhclient is available).

For now, I haven't found a simple and clean way to launch dhclient during the network startup, to select the IPv6 address (IA_NA) and reserve the IPv6 prefix (IA_PD)J. According to documentation -N and -P options should not be used together. So, I have to start IPv6 network manually. If you have a better solution...