H3C Technologies H3C S12500 Series Switches - Manual (Page 196)

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Configuring DHCPv6 relay agent
Overview
Application environment
Figure 74 Typical DHCPv6 relay agent application
A DHCPv6 client usually uses a multicast address to contact the DHCPv6 server on the local link to obtain
an IPv6 address and other configuration parameters. As shown in Figure 74 , if the DHCPv6 server
resides on another subnet, the DHCPv6 client can contact the server through a DHCPv6 relay agent. Thus,
you do not need to deploy a DHCPv6 server on each subnet.
Operation of DHCPv6 relay agent
Figure 75 DHCPv6 relay agent operation process
Take the process of rapid assignment by using two messages as an example. Figure 75 shows how the
DHCPv6 client obtains an IPv6 address and other network configuration parameters from the DHCPv6
server through the DHCPv6 relay agent.
IPv6 network
DHCPv6 server
DHCPv6 relay agent
DHCPv6 client DHCPv6 client
DHCPv6 client DHCPv6 client
(1) Solicit (contains a Rapid Commit option)
(4) Reply
DHCPv6 client DHCPv6 relay agent DHCPv6 server
(2) Relay-forward
(3) Relay-reply