Basic phase of DHCPv6 dialogue is not significantly changed comparing to its predecessors. DHCPv6 configuration is essential in four steps:
Solicit – the client looks for friendly server. Since the client does not know anything about the network sends its request to the multicast address. The request contains all its identification data (DUID and IA).
Advertise – a server sends this message to indicate that it is available for DHCP service, in response to a Solicit message received from a client. Message is sent by servers that are willing to give clients some parameters (usually only one, but there can be more).
Request – the client chooses bid, which he seems to be the best, and the appropriate server sends a request to award the offered parameters.
Reply – the whole process ends with sending the confirmation, which the server notifies the client that he actually assigned parameters.
The Procedure of DHCPv6
Multicast address allocated to the DHCPv6 procedure
FF02::1:2 all DHCPv6 agents and servers (it is link-local address !)