All dynamic addressing start with RA messages ( they are sent every 200ms )
An RA ICMPv6 is sent to all IPv6 Devices  ( FF02::1 )
Or when an RS iICMPv6  To all routers ( FF02::2 )  received from the HOST

To be able to send an receive RA and SA the command: ipv6 unicast-routing need to be configured.

There are 3 options for the router to choose how to respond to the advertisement :

1- SLAAC – No DHCPv6 ( that means that the router will provide all configuration configure on the router )
2- SLAAC – SLAAC + Stateless DHCPv6 for DNS address ( that mean that the router will provide some information but need a DHCPv6 server to provide the missing informations ex: DNS informations)
3- SLAAC – Stateful all addressing except the default gateway ( link-local address ) use DHCPv6.Server


More to come here regardings the FLAGS and configurations that go with it.

In order for the client to know that that we are using a stateful or stateless configuration all this is done on the interface configuration :

ipv6 nd managed-config-flag  = Stateful configuration.
( u will need to configure the dhcp relay destination under the interface “ipv6 dhcp relay destination “ipv6add” “outgoing interface” unless it is link-local)

ipv6 nd other-config-flag  = Stateless configuration.


ISP example :

These slides where use of LiveLessons IPV6 Fundamentals



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