Prefix Delegation for ICX DHCPv6 Servers

Prefix delegation allows a DHCPv6 server to assign prefixes selected from a global pool to DHCPv6 clients (requesting routers). The DHCPv6 client can then configure an IPv6 address on its LAN interface using the received prefix. The DHCPv6 client then sends router advertisements that include the prefix, allowing other devices to use auto-configuration to configure their own IPv6 addresses. The PD device (requesting routers) is connected to the DHCPv6 server (ICX device). The DHCPv6 server must have prefix6 configured. The PD device receives the prefix from the DHCPv6 server. The hosts connected to the PD device receive the IPv6 address in the prefix received by the PD device.

The following example assigns a range of IPv6 prefixes to a subnet. The prefix6 command is used to configure the prefix range for delegation to sub-routers.

device# configure terminal
device(config)# ipv6 dhcp6-server enable 
device(config-dhcp6)# subnet6 2001:db8:0:1::/64
device (config-dhcp6-subnet)# range6 2001:db8:0:1::129 2001:db8:0:1::254
device(config-dhcpv6-subnet)# prefix6 2001:db8:0:100::/56 2001:db8:0:f00::/56 

The following configuration example shows a sample configuration for an ICX device with the prefix delegation feature and DHCPv6 server enabled.

!
ipv6 dhcp6-server enable
 subnet6 2001:db8:0:1::/64                                        
  prefix6 2001:db8:0:100::/56 2001:db8:0:f00::/56 
  range6  2001:db8:0:1::129  2001:db8:0:1::254 
exit
!
ipv6 unicast-routing
!
interface ve 4080
 ipv6 address 2001:db8:0:1::100/6