2.8 SLAAC & DHCPv6

SLAAC + Stateless DHCPv6 Method (Server)

The stateless DHCPv6 option tells the client to use the information in the RA message for addressing, but additional configuration parameters are available from a DHCPv6 server.

This process is known as stateless DHCPv6 because the server is not maintaining any client state information (i.e., a list of available and allocated IPv6 addresses). The stateless DHCPv6 server is only providing configuration parameters for clients, not IPv6 addresses.


Enable SLAAC + Stateless DHCPv6 on a Router

Stateless DHCPv6 is enabled on a router interface using the ipv6 nd other-config-flag interface configuration command. This sets the O flag to 1.

Enable IPv6 Unicast Routing

R1(config)# ipv6 unicast-routing

Define a DHCPv6 Pool Name

R1(config)# ipv6 dhcp pool [poolname]

Define a DNS server

R1(config-dhcpv6)# dns-server [ipv6-address]

Define the domain name

R1(config-dhcpv6)# domain-name [domain]

Assign DHCPv6 Server to an Interface and enable it

R1(config)# interface [interface]
R1(config-if)# ipv6 dhcp server [poolname]

Configure ND Flag (SLAAC + Stateless DHCPv6 O Flag) and enable it

R1(config-if)# ipv6 nd other-config flag
R1(config-if)# no shutdown
R1(config-if)# exit
SLAAC + Stateless DHCPv6 Complete Configuration example
R1> enable
R1# configure terminal
R1(config)# ipv6 unicast-routing
R1(config)# ipv6 dhcp pool LAN-POOL-1
R1(config-dhcpv6)# dns-server 2001:db8:cafe:aaaa::5
R1(config-dhcpv6)# domain-name cisco.com
R1(config-dhcpv6)# exit
R1(config)#
R1(config)# interface g0/0
R1(config-if)# ipv6 dhcp server LAN-POOL-1
R1(config-if)# ipv6 nd other-config flag
R1(config-if)# exit
R1(config)#