!Receive default route via RA:
!WAN interface
interface FastEthernet 4
 ipv6 address autoconfig default

!DHCP IA NA client configuration:
!WAN interface:
interface FastEthernet4
 ipv6 address dhcp

!DHCP-PD/IA PD client configuration:
!WAN interface:
interface FastEthernet4
 ipv6 enable
 ipv6 nd ra suppress all
 ipv6 dhcp client pd dhcp-prefix

!DHCPv6 config for forwarding DNS from the ISP:
ipv6 dhcp pool LAN
 import dns-server
 import domain-name

!LAN-interface:
interface Vlan1
 ipv6 address dhcp-prefix ::0:0:0:0:1/64
 ipv6 nd other-config-flag
 ipv6 dhcp server LAN