Installing and Configuring DHCPv6 2

Overview
How DHCPv6 2.001 Works
Chapter 1 15
DHCPv6 2.001 requires relays to be set up on the client’s link when the
client and the server are on different links. Relays receive messages from
the client and forward them verbatim to a set of servers that the DHCP
domain includes. Relays forward the client’s messages to servers using
any of the following addresses:
• All DHCP Servers Site-local multicast address
• Other site-local multicast addresses set up within the DHCP domain
to include the servers in that domain
• A list of unicast addresses for servers
Figure 1-2 depicts how the client and the server, on different links,
communicate with each other.
Figure 1-2 When Client and Server Are on Different Links
The client and the server exchange messages with each other via a relay
as follows (see numbers 1,2,3,4, and 5 in Figure 1-2):
1. The client sends a DHCP SOLICIT message to the ALL DHCP Agents
address to locate servers that are able to offer the required services.
2. The relay forwards the client’s message to servers by sending
RELAY-FORW messages. The client message is encapsulated in the
RELAY-FORW message.