Switch Management Commands 1926User GuidelinesThe IPv6 DHCP service must be enabled to use this feature. Enable the IPv6DHCP service using the service dhcpv6 command. If relay-address is an IPv6global address, then relay-interface is not required. If relay-address is a link-local or multicast address, then relay-interface is required. Finally, a value forrelay-address is not specified, then a value for relay-interface must bespecified and the DHCPV6-ALLAGENTS multicast address (i.e. FF02::1:2)is used to relay DHCPv6 messages to the relay server. An IP interface (VLAN)can be configured in DHCP relay mode or DHCP server mode. Configuringan interface in DHCP relay mode overwrites the DHCP server mode and vice-versa.An IP interface configured in relay mode cannot be configured as a DHCPclient (ip address dhcp).ExampleThe following example configures VLAN 15 for DHCPv6 relay functionality.console(config)#service dhcpv6console(config)#interface vlan 15console(config-if-vlan15)#ipv6 dhcp relay destination 2020:1::1ipv6 dhcp serverUse the ipv6 dhcp server command in Interface Configuration mode toconfigure DHCPv6 server functionality on an interface. For a particularinterface DHCPv6 server and DHCPv6 relay functions are mutually exclusive.Syntaxipv6 dhcp server pool-name [rapid-commit] [preference pref-value]• pool-name — The name of the DHCPv6 pool containing stateless and/orprefix delegation parameters• rapid-commit — An option that allows for an abbreviated exchangebetween the client and server.• pref-value — Preference value — used by clients to determine preferencebetween multiple DHCPv6 servers. (Range: 0-4294967295)