3Com S7906E Configuration Manual page 437

Configuration procedure
# Enable DHCP snooping.
<SwitchB> system-view
[SwitchB] dhcp-snooping
# Specify GigabitEthernet2/0/1 as trusted.
[SwitchB] interface GigabitEthernet2/0/1
[SwitchB-GigabitEthernet2/0/1] dhcp-snooping trust
[SwitchB-GigabitEthernet2/0/1] quit
# Configure GigabitEthernet2/0/2 to support Option 82.
[SwitchB] interface GigabitEthernet2/0/2
[SwitchB-GigabitEthernet2/0/2] dhcp-snooping information enable
[SwitchB-GigabitEthernet2/0/2] dhcp-snooping information strategy replace
[SwitchB-GigabitEthernet2/0/2] dhcp-snooping information circuit-id string company001
[SwitchB-GigabitEthernet2/0/2] dhcp-snooping information remote-id string device001
[SwitchB-GigabitEthernet2/0/2] quit
# Configure GigabitEthernet2/0/3 to support Option 82.
[SwitchB] interface GigabitEthernet 2/0/3
[SwitchB-GigabitEthernet2/0/3] dhcp-snooping information enable
[SwitchB-GigabitEthernet2/0/3] dhcp-snooping information strategy replace
[SwitchB-GigabitEthernet2/0/3] dhcp-snooping information format verbose node-identifier
sysname
[SwitchB-GigabitEthernet2/0/3] dhcp-snooping information circuit-id format-type ascii
[SwitchB-GigabitEthernet2/0/3] dhcp-snooping information remote-id format-type ascii
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