Stateful DHCPv6 (DHCPv6 only)
This option is the most similar to DHCPv4. In this case, the RA message informs the client not to use the information in the RA message. All addressing information and configuration information must be obtained from a stateful DHCPv6 server. This is known as stateful DHCPv6 because the DHCPv6 server maintains IPv6 state information. This is similar to a DHCPv4 server allocating addresses for IPv4.
The M flag indicates whether or not to use stateful DHCPv6. The O flag is not involved. The following command is used to change the M flag from 0 to 1 to signify stateful DHCPv6:
Router(config-if)# ipv6 nd managed-config-flag