SNR S2940-8G-v2, Configuration Manual

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SNR S2940-8G-v2 Switch Configuration Guide
DHCPv6 Configuration
Chapter 35
DHCPv6 Configuration
35.1 Introduction to DHCPv6
DHCPv6 [RFC3315] is the IPv6 version for Dynamic Host Configuration Protocol (DHCP). It is
a protocol that assigns IPv6 address as well as other network configuration parameters such as
DNS address, and domain name to DHCPv6 client, DHCPv6 is a conditional auto address config-
uration protocol relative to IPv6. In the conditional address configuration process, DHCPv6 server
assigns a complete IPv6 address to client, and provides DNS address, domain name and other
configuration information, maybe the DHCPv6 packet can transmit through relay delegation, at last
the binding of IPv6 address and client can be recorded by DHCPv6 server, all that can enhance
the management of network; DHCPv6 server can also provide non state DHCPv6 service, that is
only assigns DNS address and domain name and other configuration information but not assigns
IPv6 address, it can solve the bug of IPv6 auto address configuration in non state; DHCPv6 can
provide extend function of DHCPv6 prefix delegation, upstream route can assign address prefix
to downstream route automatically, that achieve the IPv6 address auto assignment in levels of
network environment, and resolved the problem of ISP and IPv6 network dispose.
There are three entities in the DHCPv6 protocol - the client, the relay and the server. The
DHCPv6 protocol is based on the UDP protocol. The DHCPv6 client sends request messages to
the DHCP server or DHCP relay with the destination port as 547, and the DHCPv6 server and
relay send replying messages with the destination port as 546. The DHCPv6 client sends solicit
or request messages with the multicast address - ff02::1:2 for DHCP relay and server.
DHCPv6 Server DHCPv6 Client
Solicit (Multicast)
Advertise (Unicast)
Request (Multicast)
Reply (Unicast)
Figure 35.1: DHCPv6 negotiation
When a DHCPv6 client tries to request an IPv6 address and other configurations from the
DHCPv6 server, the client has to find the location of the DHCP server, and then request configu-
rations from the DHCP server.
1. In the time of located server, the DHCP client tries to find a DHCPv6 server by broadcasting
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