H3C Technologies H3C S12500 Series Switches - Manual (Page 204)

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Network requirements
As shown in Figure 78 , Switch B connects to a DHCPv6 server (Switch A) through GigabitEthernet 3/0/1,
a DHCPv6 client through GigabitEthernet 3/0/2, and another DHCPv6 client or an unauthorized
DHCPv6 server through GigabitEthernet 3/0/3. These three interfaces belong to VLAN 2.
Configure Switch B to do the following:
• Forward DHCPv6 reply messages received on GigabitEthernet 3/0/1 only.
• Record the IP-to-MAC mappings for DHCPv6 clients.
Figure 78 Network diagram
Configuration procedure
# Enable DHCPv6 snooping globally.
<SwitchB> system-view
[SwitchB] ipv6 dhcp snooping enable
# Add GigabitEthernet 3/0/1, GigabitEthernet 3/0/2, and GigabitEthernet 3/0/3 to VLAN 2.
[SwitchB] vlan 2
[SwitchB-vlan2] port gigabitethernet 3/0/1 gigabitethernet 3/0/2 gigabitethernet 3/0/3
# Enable DHCPv6 snooping for VLAN 2.
[SwitchB-vlan2] ipv6 dhcp snooping vlan enable
[SwitchB-vlan2] quit
# Configure GigabitEthernet 3/0/1 as a DHCPv6 snooping trusted port.
[SwitchB] interface gigabitethernet 3/0/1
[SwitchB-GigabitEthernet 3/0/1] ipv6 dhcp snooping trust
Verifying the configuration
After the preceding configuration is complete, connect GigabitEthernet 3/0/2 to the DHCPv6 client,
connect GigabitEthernet 3/0/1 to the DHCPv6 server (Switch A), and connect GigabitEthernet 3/0/3
to an unauthorized DHCPv6 server. The DHCPv6 client obtains an IPv6 address from Switch A, but
cannot obtain any IPv6 address from the unauthorized DHCPv6 server. You can use the display ipv6
dhcp snooping user-binding command to view the DHCPv6 snooping entries on Switch B.