D-Link DES-3550 Command Line Interface Reference Manual page 184

Example usage:
To configure DHCP relay option 82 state:
To configure DHCP relay option 82 check:
To configure DHCP relay option 82 policy:
DES-3550 Layer 2 Fast Ethernet Switch
DES-3550:4#config dhcp_relay option_82 state enable
Command: config dhcp_relay option_82 state enable
Success.
DES-3550:4#
DES-3550:4#config dhcp_relay option_82 check enable
Command: config dhcp_relay option_82 check enable
Success.
DES-3550:4#
DES-3550:4#config dhcp_relay option_82 policy replace
Command: config dhcp_relay option_82 policy replace
Success.
DES-3550:4#
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