F3726, F3211, F3174, R5135, R3816-HP Firewalls and UTM Devices Network Management Configuration Guide-6PW100

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Figure 367 Using the Renew message for address/prefix lease renewal
As shown in 2889HFigure 368, if the DHCPv6 client receives no response from the DHCPv6 server after sending
out a Renew message at T1, it multicasts a Rebind message to all DHCPv6 servers at T2 (that is, when 80%
preferred lifetime expires). Then the DHCPv6 server responds with a Reply message, informing the client
about whether or not the lease is renewed.
If the DHCPv6 client receives no response from the DHCPv6 servers, the client stops using the
address/prefix when the valid lifetime expires.
Figure 368 Using the Rebind message for address/prefix lease renewal
For more information about the valid lifetime and the preferred lifetime, see "Configuring IPv6 basics."
232B
Stateless DHCPv6 configuration
After obtaining an IPv6 address/prefix, a device can use stateless DHCPv6 to obtain other configuration
parameters from a DHCPv6 server. This application is called stateless DHCPv6 configuration.
With an IPv6 address obtained through stateless address autoconfiguration, a device automatically
enables the stateless DHCPv6 function after it receives an RA message with the managed address
configuration flag (M flag) set to 0 and with the other stateful configuration flag (O flag) set to 1.
Stateless address autoconfiguration means that a node automatically generates an IPv6 address based
on the information obtained through router/prefix discovery. For more information, see "Configuring
IPv6 basics."
As shown in
2890HFigure 369, stateless DHCPv6 operates as follows:
1. The DHCPv6 client multicasts an Information-request message to the multicast address of all
DHCPv6 servers and DHCPv6 relay agents. The Information-request message contains an Option
Request option, specifying the configuration parameters that the client requests from the DHCPv6
server.
2. After receiving the Information-request message, the DHCPv6 server returns to the client a Reply
message containing the requested configuration parameters.
3. The client checks the Reply message. If the obtained configuration parameters match those
requested in the Information-request message, the client performs network configuration with the